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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

QUALANOD

LISBOA ● dezembro de 2015

I & D MATERIAIS RELATÓRIO 413/2015 – DM/NMM


Title STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Authorship MATERIALS DEPARTMENT I. Rute Fontinha Assistant Researcher , Metallic Materials Division Nuno Garcia Senior Technician, Metallic Materials Division

Copyright © Laboratório Nacional de Engenharia Civil, I. P. Av. do Brasil 101 • 1700-066 Lisboa e-mail: lnec@lnec.pt www.lnec.pt Relatório 413/2015 Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Abstract Aiming to ban the use of carcinogenic Cr(VI) compounds in the aluminium surface treatment industry, a new Cr-free immersion test method (PA), based on the previous chromic-phosphoric acid immersion test (CPA), was proposed to assess sealing quality of anodic oxidation coatings of aluminium and its alloys. This new method was under trial within QUALANOD inspection laboratories from 2013 to 2014, to evaluate its applicability to replace the referee test that uses Cr(VI) compounds (CPA). Since the beginning of 2015, following instructions from QUALANOD Technical Committee, the new test has been used solely as referee test in QUALANOD’s inspections as well as for in-house quality control of anodizing plants. First, the present report comprises all the data collected during 2013 and 2014 inspections carried out in several countries relative to both sealing test methods and to the results of the comparative analysis done to evaluate the new test method applicability and critical parameters. Furthermore, this report comprises another comparative analysis, based only on results from Portuguese inspections carried out from 2014 to 2015, aiming to evaluate the influence of anodization variables (anodizing temperature, current density and sealing time), and also of the reduction of the PA test immersion time, on the mass loss differences yielded by both test methods. Finally, the results of a complementary study carried out by LNEC to evaluate of the effect of PA test solutions temperature variations on anodic coating mass loss are also presented, as well as the results of bare substrate dissolution tests performed on two aluminium alloys (EN AW-6063 and EN AW-5005), following the currently used PA test experimental procedure. Keywords:

Anodized aluminium / QUALANOD / Sealing quality tests

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

ESTUDO DO NOVO MÉTODO DE ENSAIO ISENTO DE CRÓMIO PARA A AVALIAÇÃO DA QUALIDADE COLMATAGEM DOS REVESTIMENTOS DE OXIDAÇÃO ANÓDICA Relatório Final

Resumo Tendo como objetivo a eliminação do uso de compostos de Cr(VI) – carcinogénico – na indústria do tratamento de superfícies do alumínio, foi proposto pelo LNEC um novo método de ensaio isento de crómio (PA), baseado no anterior método de imersão em ácido fosfocrómico (CPA), para a avaliação da qualidade da colmatagem do alumínio anodizado. Este novo método foi experimentado no âmbito de inspeções QUALANOD realizadas durante os anos de 2013 e 2014, para avaliação da sua adequação como substituto do método de referência em vigor (CPA), que usava compostos de Cr(VI). Desde o início de 2015 que, seguindo instruções do Comité Técnico da QUALANOD, apenas o novo método de ensaio tem sido usado como método de referência nas inspeções QUALANOD, assim como no controlo de qualidade interno das fábricas de anodização. O presente relatório reúne todos os dados colhidos durante inspeções QUALANOD realizadas nos anos de 2013 e 2014, em diversos países, relativos aos dois métodos de ensaio da qualidade da colmatagem do revestimento anódico e apresenta a sua análise comparativa, realizada para avaliação da aplicabilidade do novo método e respetivos parâmetros críticos. Adicionalmente, neste relatório é apresentada uma outra análise comparativa dos resultados dos dois métodos, baseada apenas nos resultados das inspeções portuguesas realizadas desde o início de 2014 até ao fim do primeiro semestre de 2015, que teve como objetivo avaliar a influência de parâmetros do processo de anodização (temperatura de anodização, densidade de corrente e tempo de colmatagem) e da redução do tempo de imersão na solução do ensaio PA, na diferença das perdas de massa obtidas pelos dois métodos experimentais. Finalmente, são apresentados para o novo método de ensaio (PA), os resultados dum estudo complementar realizado pelo LNEC com o objetivo de avaliar o efeito da variação da temperatura das soluções de ensaio nos valores da perda de massa do revestimento anódico, assim como os efeitos na dissolução do substrato de alumínio não anodizado, de dois tipos de liga (EN AW-6063 and EN AW-5005), do procedimento experimental correntemente usado. Palavras-chave:

II

Alumínio anodizado / QUALANOD / Ensaios de qualidade da colmatagem

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Executive Summary Background The assessment of aluminium anodic oxide coatings sealing quality has been done by the chromic/phosphoric acid (CPA) mass loss test, since long time accepted as referee test by the European Quality label QUALANOD. However, due to the fact that the CPA test solution contains the carcinogenic hexavalent chromium (Cr(IV)) foreseen to be banned from industry till September 2017, alternative tests have been sought. For the purpose of finding an alternative chromium-free sealing test method, several experimental studies have been carried out in the last years, involving several acid test solutions. The results of those studies pointed to the test using the same phosphoric acid solution as the CPA test, but without the chromium oxide addition, as the most promising candidate to replace it. This new Cr-free phosphoric acid immersion test method (PA) was under trial within QUALANOD inspection laboratories from 2013 to 2014, to evaluate its applicability and critical factors. Based on the results of this trial, since the beginning of 2015, following instructions from QUALANOD Technical Committee, The PA test has been used as referee test in QUALANOD’s inspections as well as for in-house quality control in anodizing plants. Meanwhile, a proposal for a new standard to be developed specifying a new test using only a th

phosphoric acid solution was presented at the 28 meeting of ISO/TC 79/SC 2 "Light metals and their alloys/Organic and anodic oxidation coatings on aluminium" held in Berlin on 2012. This was accepted and later the ISO/TC 79/SC 2 committee decided to review the ISO 3210 standard to include this test solution without Cr(VI). This revision process is still on going and is expected to be concluded during 2017.

Study Findings This Executive Summary resumes the key findings of the comparative analysis performed to PA and CPA tests mass loss data from QUALANOD product inspections, and of complimentary studies on PA test experimental parameters.

Analysis of Data from QUALANOD Inspections (2013 - 2014) The analysis of the PA and CPA tests mass loss data collected in QUALANOD inspections addressed the effects of different factors like anodic coating production conditions (sealing process, thickness class, colour), test specimens’ characteristics (alloy, section type) and test solution stirring on the correlation between both mass loss test methods results, aiming to evaluate the new test method applicability and critical parameters.

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Data treated was collected during two years (2013 and 2014) in product inspections to anodizing plants carried out in eleven European countries and at China. Turkey, Spain, Portugal and Italy are the main contributors of data. A total of valid 331 inspections reports were received, comprising a total 391 pairs of mass loss results reported. The most frequent characteristics of the test specimens of this survey were: anodic coating not coloured, of 15 µm thickness class, hot water sealed and being cut from EN AW-6063 alloy profiles of solid section. The results obtained showed the following: •

CPA and PA mass loss test methods evidenced similar trends: the PA test follows CPA test response. As expected, the PA test tended to yield larger mass loss values than the CPA test. The mass loss differences between the two test methods showed to be significant and tended to increase with the mass loss value. In 91% of tests carried out, the mass loss differences 2

obtained were positive and less than 10 mg/dm ; •

Disregarding the results with a probability of occurrence lower than 1%, the average mass 2

2

loss difference was 4,0 mg/dm with a standard deviation of 3,0 mg/dm ; •

The sealing process may influence the correlation between the two mass loss tests: cold sealed test specimens tended to presented lower average mass loss differences than the other types of sealed specimens;

Test specimens of hollow section led to slightly higher average mass loss differences. Anyway the presence of uncoated surfaces was not as influential on the PA test results as expected: only those with more than 20% of uncoated area showed more significant higher mass loss differences;

Factors like test solution stirring, alloy, anodic coating thickness class and colour did not show any particular influence on mass loss differences;

If the PA test had been used, instead of the CPA test, to assess anodic coating sealing quality in the QUALANOD inspections survey, the number of negative results would have increased 2

significantly: four times, considering the acceptance limit of 30,0 mg/dm ; to almost the 2

double, considering the acceptance limit of 35,0 mg/dm . However, it should be noticed that with this last limit, one CPA based negative inspection would have passed, what turned this higher acceptance mass loss limit unappropriated.

Analysis of Additional Data from Portuguese QUALANOD Inspections (2014 - 2015) The analysis of the PA and CPA tests mass loss data collected in Portuguese QUALANOD inspections carried out from 2014 to 2015 addressed the effects of anodization variables (anodizing temperature, current density and sealing time), and of the reduction of the PA test immersion time, on the correlation between both mass loss test methods.

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The results obtained showed the following: •

Only the current density showed some effect on the PA and CPA tests correlation: mass loss differences between the two test methods increased when anodizing current density decreased;

The reduction of the immersion time in the phosphoric acid test solution from 15 to 13 minutes led to PA test mass losses still higher, but closer to those of the CPA test.

Complimentary studies on the PA test The complimentary studies included in this report aimed to evaluate the effect of PA test solutions (predip and phosphoric acid) temperature variations on anodic coating mass loss. The results obtained demonstrated that: •

The predip solution temperature variations have very little influence on the PA test results;

The variation of phosphoric acid solution temperature within the permitted range (38ºC±1ºC) may contribute, in lesser extent, to the mass loss results dispersion.

Another aspect evaluated in these studies was the PA test solutions attack of uncoated alloys. This was achieved by measuring the dissolution of test specimens of two alloys (EN AW-6063 and EN AW5005) after immersion in the PA test solutions, for the same testing times. The results obtained 2

indicate that the mass loss of alloy EN AW-5005 was 9,3 mg/dm , while for the alloy EN AW-6063 was 2

5,0 mg/dm .

Overall effectiveness of PA test On the whole, the different comparative analysis of the results of PA and CPA mass loss tests performed herein, confirmed that the PA mass loss test can replace the CPA mass loss test in the assessment of anodic coatings sealing quality. However, due to the fact that PA test effectively leads to higher mass losses, could be more appropriate to perform this test with the immersion time in the phosphoric acid test solution reduced from 15 to 13 minutes, as established in the QUALANOD Specifications’ Update Sheet nº20. The results obtained indicate that the PA mass loss test, in principle, shall be preferably performed with test specimens of solid section, but also point to the possibility of its application to hollow section test specimens under certain circumstances. It was also observed that only imposing, for the PA test, the same acceptance limit of the CPA test 2

(30,0 mg/dm ) would assure (at least) the same level of quality of the CPA test. However, even with the reduced testing time, it is foreseen that this new requirement would turn the sealing quality control more demanding in practice, especially for those anodizing plants with the hot water sealing process.

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Index of Contents 1 | Introduction ......................................................................................................................................1 2 | Analysis of PA and CPA Mass Loss Tests Data from QUALANOD’s Inspections (2013 - 2014) ......................................................................................................................................................3 2.1 Participants ...........................................................................................................................3 2.2 Mass loss tests conditions and data required in the reports .................................................3 2.3 Characterization of reported data .........................................................................................4 2.4 Comparative analysis of mass loss results ...........................................................................7 2.4.1 Outlying or erroneous results .................................................................................13 2.4.2 Influencing factors on mass loss results ................................................................15 2.5 Impact of PA mass loss test on product inspections results ...............................................24 3 | Analysis of PA and CPA Mass Loss Tests Additional Data from Portuguese QUALANOD’s Inspections (2014 - 2015) ...............................................................................................25 3.1 Influence of production factors on mass loss results dispersion ........................................25 3.2 Influence of reducing immersion time in the phosphoric acid solution on mass loss differences ...................................................................................................................26 4 | Complimentary studies on PA test ................................................................................................29 4.1 Influence of PA test solutions temperature on mass loss results .......................................29 4.1.1 Effect of the nitric acid (predip) solution temperature variation .............................30 4.1.2 Effect of the phosphoric acid solution temperature variation .................................31 4.2 Aluminium alloy dissolution in the PA test solutions ...........................................................33 5 | Conclusions ...................................................................................................................................35 References .............................................................................................................................................38 Annexes .........................................................................................................................................41 ANNEX I Forms of the inspection reports ..............................................................................................43 ANNEX II Results from QUALANOD’s Product Inspections Survey (2013-2014) .................................47 ANNEX III List of Inspected Anodizing Plants ........................................................................................59 ANNEX IV Statistical Analysis ................................................................................................................63 ANNEX V Additional Data from Portuguese QUALANOD’s Product Inspections Survey (2014-2015) .....................................................................................................................69 ANNEX VI Results of the Complimentary Studies on PA test................................................................73

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Index of Figures Figure 2.1 – Test specimens’ distribution (in %) by country.....................................................................5 Figure 2.2 – Test specimens’ distribution (in %) by production characteristics (sealing process, anodic coating thickness class and colour), test specimen section type, alloy and test solution stirring................................................................................................6 Figure 2.3 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants (all data) ................................................................................................................................8 Figure 2.4 – Frequency distribution of (PA – CPA) mass loss differences obtained in QUALANOD inspections to anodizing plants (all data) ........................................................9 Figure 2.5 – Average (PA – CPA) mass loss differences and respective standard deviations (left) for several ranges of CPA test results and distribution of the number of CPA tests with results within the same ranges (right) ..........................................................9 Figure 2.6 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by country ............................................................................................................11 Figure 2.7 – Frequency distribution of (PA – CPA) mass loss differences obtained in QUALANOD inspections to anodizing plants with discarded points signed .......................14 Figure 2.8 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by sealing process ...............................................................................................16 Figure 2.9 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by anodic coating thickness class .......................................................................17 Figure 2.10 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by anodic coating colour ......................................................................................18 Figure 2.11 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test specimens section type ...........................................................................19 Figure 2.12 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test specimens alloy .......................................................................................20 Figure 2.13 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test solution stirring .........................................................................................21 Figure 2.14 – Effect of the percentage of test specimen’s uncoated area on (PA-CPA) mass loss differences ...................................................................................................................23 Figure 3.1 – (PA-CPA) mass loss differences distribution according to several production parameters - values shown in a box refer to the operating conditions globally recommended by QUALANOD for each parameter ...........................................................25 Figure 3.2 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants during 2013/2014 (PA15min) and 2015(PA13min) .............................................................27 Figure 4.1 – PA mass loss test results for different predip solution temperatures .................................31 Figure 4.2 – Average PA mass loss test results and respective standard deviation for different phosphoric acid solution temperatures .................................................................32 Figure 4.3 – Average (PA-CPA) mass loss differences vs CPA mass losses of the several anodic coating types for different phosphoric acid solution temperatures ..........................32

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Index of Tables Table 2.1 – List of QUALANOD Testing institutes participating and respective countries of intervention............................................................................................................................3 Table 2.2 – Standard test solutions and conditions of the two mass loss tests experimental procedure ..............................................................................................................................4 Table 2.3 – Test specimens’ distribution by country and the number of respective inspected plants .....................................................................................................................................5 Table 2.4 – Test specimens’ distribution according to sealing process and thickness class ...................5 a) Table 2.5 – Test specimens’ distribution by anodic coating colour ........................................................5 Table 2.6 – Test specimens’ characteristics distribution according to section type and alloy .................6 Table 2.7 – Test specimens’ distribution according to test solution stirring .............................................6 2 Table 2.8 – Average (PA-CPA) mass loss differences (in mg/dm ) obtained in the QUALANOD survey ............................................................................................................10 2 Table 2.9 – (PA-CPA) mass loss differences (in mg/dm ) obtained by country .....................................12 2 Table 2.10 – Average (PA-CPA) mass loss differences (mg/dm ) with respect to sealing process and thickness class ...............................................................................................22 2 Table 2.11 – Average (PA-CPA) mass loss differences (mg/dm ) with respect to anodic a) coating colour ....................................................................................................................22 2 Table 2.12 – Average (PA-CPA) mass loss differences (mg/dm ) with respect to test specimens section and alloy ...............................................................................................22 2 Table 2.13 – Average (PA-CPA) mass loss differences (mg/dm ) with respect to test solution stirring .................................................................................................................................22 2 2 Table 2.14 – Application of PA test, with the acceptance limits of 35 mg/dm or 30 mg/dm , to assess anodic coatings sealing quality within the 2013-2014 QUALANOD inspections ..........................................................................................................................24 Table 4.1 – Test specimens thickness classes required and other production parameters by anodic coating type and their distribution according to the Test program ..........................29 Table 4.2 –Test solutions temperature and immersion time used in the Test program .........................30 1 Table 4.3 – Aluminium alloys composition (in %) according to EN 573-3 [19] .....................................33 Table 4.4 – Aluminium alloys mass loss in the PA test ..........................................................................34

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Introduction

Aluminium alloys find large use in architectural applications, mostly in building components, usually surface coated to achieve a desired aesthetical aspect and protection against corrosion. Anodization, an industrial electrolytic process that promotes the artificial growth of an aluminium oxide layer, is one of the most common surface treatments used to protect architectural aluminium components against corrosion. To assure the expected service life, the aluminium anodic oxide coatings produced for architectural applications, based on the sulphuric acid process at low temperatures, require appropriate sealing of their porous outer layer [1]. Sealing increases resistance to corrosion and to other types of weathering damage of anodized aluminium surface [2][3]. The assessment of aluminium anodic oxide coatings sealing quality has long been done by acid immersion tests. The most effective and widely accepted as referee test [4][5], namely by European Quality label QUALANOD [6], is the chromic/phosphoric acid (CPA) mass loss test, presently described in the standard ISO 3210 [7]. However, due to the fact that the CPA test solution contains the carcinogenic hexavalent chromium (Cr(IV)), foreseen to be banned from industry till September 2017[8], alternative tests have been sought. For the purpose of finding an alternative chromium-free sealing test method, several experimental studies have been carried out in the last years, involving several acid test solutions [5][9][10]. The results obtained in those preliminary studies pointed to the test using the same solution of phosphoric acid as CPA test but without the chromium oxide addition, as the most promising candidate to replace it. This finding is consistent with the evidence already found that mechanisms of dissolution may depend both on acidity and on the type of anion present [5]. Following the results of the preliminary studies, a new sealing test method designated by phosphoric acid (PA) test, based on CPA test experimental procedure, was proposed to QUALANOD and it had been under trial within QUALANOD inspection laboratories from 2011 till 2014: first it was included in the 2011 Round Robin Inter-laboratory test [11], then again in the 2013 Round Robin Inter-laboratory test [12], and in the same year it started to be used in addition to the mass loss reference test (CPA test) within QUALANOD inspections to gather experience of its application in an industrial context [13]. This last enlarged comparative survey was extended till the end of 2014. These results were partially presented at the meeting of the QUALISURFAL Anodising Section held in Geneva on 15 September of 2014. Finally, based on all the collected data, the Technical Committee decided to modify section 2.3.3 of QUALANOD Specifications in order to the PA chromium-free test be used as the exclusive sealing quality referee test, starting from January of 2015. It had been decided to keep the limit value of 30.0 mg/dm², however, the immersion time in the test solution should be shifted from 15 minutes to 13 minutes. Additionally, a restriction to the application of the new method was imposed based on the

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percentage of test specimen’s uncoated area and respective dissolution rate [14]. The PA test acceptance limit and restrictions of use were based on the results of some complimentary studies carried out to address questions relative to PA test performance, namely those concerning the extent of uncoated aluminium surface attack, raised by the fact that PA test solution does not have any corrosion inhibitor added like CPA test has (chromium (VI) oxide), and on the extent of mass loss differences found between both test methods in the previous surveys [15]. Meanwhile, following the PA test preliminary results from Portugal, Italy and China, a proposal for a new standard to be developed specifying a new test using a phosphoric acid solution was presented th

at the 28 meeting of ISO/TC 79/SC 2 "Light metals and their alloys/Organic and anodic oxidation coatings on aluminium" held in Berlin on 2012 [16]. This was accepted and later the ISO/TC 79/SC 2 committee

decided

to

review

the

ISO

3210

standard

to

include

test

solution

without

Chromium(VI) [17]. This revision process is still going on and is expected to be concluded during 2017. The present report complements the previous documents comprising all the data sent to LNEC relative to both sealing test methods (PA and CPA tests), collected during 2013 and 2014 QUALANOD inspections carried out in different anodizing plants from Europe and China, as well as the comparative analysis done to evaluate the new test method applicability and critical parameters. Furthermore, based only on results from Portuguese inspections carried out from 2014 to 2015, another comparative analysis to the correlation between PA and CPA tests was done aiming to evaluate the possible influence of anodization variables (anodizing temperature, current density and sealing time) on the dispersion of the mass loss differences yielded by both test methods. The results of 2015’ Portuguese inspections were further used to evaluate the consequences of reduction of the PA test immersion time in the phosphoric acid solution to 13 minutes on the magnitude of the two mass loss tests differences, in comparison to what was had been obtained in the 2013-2014 survey, with an immersion time of 15 minutes in the same acid solution. Finally, this report also presents the results of two complementary studies carried out by LNEC to evaluate of the effect of PA test solutions (nitric acid (predip) and phosphoric acid) temperature variations on anodic coating mass loss, as well as to assess the effect of uncoated aluminium dissolution in the PA test solutions for two different aluminium alloys (EN AW-6063 and EN AW-5005), following the PA test experimental procedure currently in use.

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Analysis of PA and CPA Mass Loss Tests Data from QUALANOD’s Inspections (2013 - 2014)

2.1

Participants

Data treated in this report was collected during two years (2013 and 2014) from product inspections to anodizing plants carried out in eleven European countries and at China. This enlarged survey involved ten testing institutes which are listed in Table 2.1. Table 2.1 – List of QUALANOD Testing institutes participating and respective countries of intervention Testing institute

Acronym

Country of intervention

AMAG

Austria

AAG

Greece and Cyprus

VEKOR

Hungary and Slovakia

QUALITAL

Italy

IMP ITB

Poland

LNEC

Portugal

QUALESPAÑA

Spain

EMPA

Switzerland

Metaltek Teknoloji

METALTEK

Turkey

IFO China - Hangzhou Ifo Surface Trearment Tecnology Co., ldt

IFO-China

China

Austria Metall AG Aluminium Association of Greece NPC. Vekor Korrózióvédelmi, Analitikai Kft. Instituto di Certificazione Industriale dell’ Alluminio ed Altri Materiali Institut Mechaniki Precyzyjnej Instytut Techniki Budowlanej Laboratório Nacional de Engenharia Civil QUALESPAÑA EMPA- Swiss Federal Laboratories for Materials Science & Technology

Except for Austria and China that have only sent reports during 2014, all the other countries have reported data during the two years of this survey.

2.2

Mass loss tests conditions and data required in the reports

The CPA mass loss test is the phosphoric acid/chromic acid immersion test stipulated at the time in the QUALANOD specifications [6] as the sealing quality reference test method, which procedure is described in the EN ISO 3210:2010 standard as Method 2 [7]. This method includes a “predip” step in a diluted nitric acid aqueous solution before immersion in the acid test solution. A maximum mass loss 2

of 30 mg/dm was required by QUALANOD for the anodic coating to be considered proper sealed. The PA mass loss test method procedure followed also the EN ISO 3210:2010 – Method 2 instructions, except for the addition of chromium (VI) oxide (corrosion inhibitor), to the acid test solution. The standard test conditions of the two sealing test methods are resumed in Table 2.2.

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Table 2.2 – Standard test solutions and conditions of the two mass loss tests experimental procedure Test Method

Test solutions

Composition of phosphoric acid (pa) solution

Temperature of pa solution

Immersion time on pa solution

CPA (EN ISO 3210 – Method 2)

Nitric acid (predip) + Phosphoric acid / chromic acid

35 ml phosphoric acid + 20 g chromium (IV) oxide (per litre)

38ºC±1ºC

15 min

PA

Nitric acid (predip) + Phosphoric acid

35 ml phosphoric acid (per litre)

38ºC±1ºC

15 min

Specific formularies were designed by QUALANOD and sent to the inspectors for reporting results of the two mass loss tests carried out in the product inspections (Annex I). In these documents, besides mass loss values of both tests, it was also required to give information about the following: -

test specimen: total and coated area, cross-section design and alloy type;

-

test solutions: previously dissolved mass and stirring of phosphoric acid solution;

-

anodic coating production conditions: sealing process and thickness class;

-

anodizing plant: company name and location;

-

inspection date.

From the beginning of 2014, based on the analysis of data reported in 2013 [13], it was additionally required: 2

-

test specimen: surface mass loss (mg/dm );

-

anodic coating production conditions: colour and measured thickness;

-

anodizing plant: license number.

An Access® database was developed to store and manage all data from product inspections sent by QUALANOD General Secretary. The designed database correlates the results from CPA and PA tests, as well as differences between the mass losses of the two methods, addressing the effects of different factors on both test methods like anodic coating production conditions, test conditions or specimen details [13].

2.3

Characterization of reported data

In some reports the information about mass loss results, test specimens or test solutions characteristics was incomplete or misunderstood. Obviously erroneous data were investigated and corrected or discarded. A total of valid 331 inspections reports were received, from which 391 pairs of mass loss results were reported. All the correspondent data is presented in the Annex II. The list of the inspected anodizing plants is presented in Annex III. Although part of the results of the PA and CPA tests survey had already been reported in 2013 [13], it was decided to include all the results received in the comparative analysis of the two mass loss tests done herein. The last set of QUALANOD inspections’ mass loss tests results, with data referent to late 2014’ inspections, was sent to LNEC in April of 2015.

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Based on the information included in the inspections’ reports, it is possible to obtain the mass loss tests results distribution in what refers to its provenience (country), test specimens’ production conditions (sealing process, thickness class, colour) and characteristics (alloy, section type), and test solution stirring. These distributions are presented in Tables 2.3 to 2.7 and in the charts of Figures 2.1 and 2.2. Table 2.3 – Test specimens’ distribution by country and the number of respective inspected plants Austria Cyprus Greece Hungary Italy No. of test specimens Inspected Plants

Portugal Poland Slovakia Spain Switzerland

Turkey China

4

4

11

10

46

88

3

13

76

10

118

8

4

1

3

1

28

7

3

2

22

3

35

5

The majority of the reported results belong to four countries. Three of which are also those with the largest number of licensed plants. However, in the case of Portugal, the relative high number of results reported derives mainly from the fact that the mass loss tests were carried out in duplicate for each inspection, during most of the time of the surveyed period.

Figure 2.1 – Test specimens’ distribution (in %) by country

Table 2.4 – Test specimens’ distribution according to sealing process and thickness class Sealing process

No. of test specimens

Thickness class

Steam

Hot water

Medium-T

Cold

5 µm

10 µm

15 µm

20 µm

25 µm

2

238

19

132

10

149

198

25

9

Table 2.5 – Test specimens’ distribution by anodic coating coloura) Black

Bronze

Medium Bronze

Yellow

Inox

Natural

Opaque white

28

6

2

7

44

44

No. of test 6 specimens a) Only reported during 2014

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Table 2.6 – Test specimens’ characteristics distribution according to section type and alloy Alloya)

Section Type Solid No. of test 277 specimens a) According to EN 573-3:

Hollow

Unknown

EN AW 6060

EN AW 6063

EN AW 5005

Unknown

67

47

167

213

2

12

Table 2.7 – Test specimens’ distribution according to test solution stirring

No. of test specimens

Stirred

Not stirred

375

16

Figure 2.2 – Test specimens’ distribution (in %) by production characteristics (sealing process, anodic coating thickness class and colour), test specimen section type, alloy and test solution stirring

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Information about test specimens’ colour has less data (it refers solely to 137 tests specimens) because this information was only required in 2014. The colour labels chosen are those written in the inspection’s reports. Therefore, although terms like “opaque white” and “natural” may refer both to the same (not) coloured finishing, it was decided to keep them in separate. In what concerns test specimens’ characteristics, based on data distributions presented, it was verified that the test specimens of this survey are mainly not coloured, with an anodic coating thickness of 15 µm class, hot water sealed and were cut from EN AW-6063 alloy profiles of solid section.

2.4

Comparative analysis of mass loss results

The comparative analysis of the PA and CPA mass loss tests results was carried out through the calculation of the differences between the mass losses obtained by the two test methods. Thus, it was necessary to calculate the mass loss per coated area (generically referred as mass loss) of each test specimen, using the absolute mass loss values reported and test specimens’ coated area. This was done for all countries, except for Italy, that only reported the mass loss per coated area. There were a few cases in which only the total area was indicated in the reports, for those cases it was assumed that the coated area was equal to the total area since they all corresponded to test specimens of solid section. Once calculated the PA and CPA tests mass losses, the mass loss differences between them could be determined. The results of these calculations are presented in the graphs shown in Figure 2.3 and the respective values were included in the Annex II, along with the correspondent inspection’s data. The first graph of Figure 2.3 presents the correlation between PA and CPA tests mass loss values. 2

The CPA test results are mostly below the 30,0 mg/dm (the maximum permissible mass loss to consider the anodic coating proper sealed). This was expected, since this survey only included test specimens selected within QUALANOD’s product inspections. Only nine CPA tests yielded mass losses above that maximum limit, which represent 2,3% of the total CPA tests. The CPA test mass 2

2

losses reported ranged from 0,01 mg/dm to 70,4 mg/dm . The results of the PA test follow the trend of the CPA test, in general, with higher mass loss values. It was verified that thirty six PA tests yielded 2

mass losses above 30,0 mg/dm , corresponding to 9,2% of the total number of PA tests. The PA test 2

2

mass losses reported ranged from 0,01 mg/dm to 66,8 mg/dm . According to the respective trend lines drawn on the first graph of Figure 2.3, the two mass loss tests results tend to diverge for higher mass loss values. In fact, the differences between the mass losses obtained in this two test methods, plotted on the second graph of Figure 2.3, show a slight tendency to increase with the CPA mass loss value. However, the values of these mass loss differences show a large dispersion; even negative values were obtained, what was not expected, since the PA test solution should be more aggressive than the CPA test solution, due to the absence of the inhibitive action of the chromium(VI) ions. According to the calculations done, the differences between the mass 2

2

loss values of the two test methods ranged from (-4,2) mg/dm to 28,4 mg/dm . Nevertheless, 91% of 2

these differences are positive and less than 10 mg/dm .

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Mass loss difference between PA and CPA tests, mg/dm2

30 25 20 15 10 5 0 -5 -10 0

20

40

60

80

100

Mass loss of CPA test (ISO 3210-Method 2), mg/dm2 Figure 2.3 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants (all data)

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The distribution of the two tests mass losses differences values is represented by the histogram of Figure 2.4. This histogram pattern indicates that mass losses differences have a unimodal, slightly left 2

2

skewed distribution. The mode is at the interval of 2 mg/dm till 3 mg/dm (exclusive). According to this distribution, the highest values (on the right side of the chart) are possible outliers.

Figure 2.4 – Frequency distribution of (PA – CPA) mass loss differences obtained in QUALANOD inspections to anodizing plants (all data) 2

2

Globally, the average mass loss difference is 4,2 mg/dm with a standard deviation of 3,7 mg/dm . However, this average may depend on the range of mass loss values considered, showing a tendency to increase with it, despite of the large dispersion associated, as shown by the graph on the left side of Figure 2.5. In this graph, the average mass loss difference and respective standard deviation interval were plotted for several ranges of CPA mass loss values. Information about the number of tests with CPA mass loss results within the same ranges is given in the bar chart presented on the right side of the Figure 2.5.

Figure 2.5 – Average (PA – CPA) mass loss differences and respective standard deviations (left) for several ranges of CPA test results and distribution of the number of CPA tests with results within the same ranges (right)

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Table 2.8 presents the global and the annual average mass loss differences and respective standard deviations obtained in the QUALANOD inspections survey, considering all data or excluding the data with negative differences. Table 2.8 presents also the average mass loss differences and respective standard deviations according to the CPA test result and the number of CPA tests considered. Table 2.8 – Average (PA-CPA) mass loss differences (in mg/dm2) obtained in the QUALANOD survey Global Source data Average

Std. Dev.

Data from 2013-2014

4,2

± 3,7

Only data from 2014

3,7

Only data from 2013 CPA mass loss ≤ 30.0 mg/dm2 (2013-2014) CPA mass loss > 30.0 mg/dm2 (2013-2014)

Number of CPA tests

Excluding all negative differences

Number of CPA tests

Average

Std. Dev.

391

4,4

±3,6

376

±2,9

192

3,8

±2,8

188

4,6

±4,4

199

5,0

±4,2

188

4,1

±3,7

382

-

-

-

6,3

±6,4

9

-

-

-

The analysis of Table 2.8 contents reveals that annual average mass loss difference decreased almost 20% from 2013 to 2014, possibly due to increased practice. In relation to CPA test results, a rise of 50% in the average mass loss difference was found when only the negative inspections (CPA 2

mass loss > 30,0 mg/dm ) are considered. One of the most relevant aspects observed in the comparison of both mass loss tests results is the relative high dispersion of the mass loss differences found between the two test methods, Consequently, the standard deviations affecting the several average values calculated were close to the respective averages and, in general, increased with the number of tests performed and the mass loss values (Table 2.8, Figure 2.5). Notwithstanding this, it is worthwhile to notice that the standard deviations values are not very distant from the values of the global reproducibility standard deviation of the PA and CPA tests determined in the last QUALANOD inter-laboratory test [12], which were (for 2

2

2

mass losses below 30,0 mg/dm ): 3,1 mg/dm and 2,5 mg/dm , respectively. Considering the results dispersion observed, a statistic test - t Test: paired two sample for means (Annex IV) - was applied to the two sets of data to determine if the differences between the two test methods results are significant or not. The results obtained are presented in the Annex IV. It was found that the two test methods led to statistically significant mass loss differences, even for the higher 2

mass losses (CPA mass loss above 30 mg/dm ). Therefore the comparative analysis of the two sets of mass loss data carried out proceeded with the purpose of identifying possible influence factors on the mass loss differences. First, the possible influences of the testing laboratory or of the producer (anodizing plant) were evaluated. In Figure 2.6 the correlation between PA and CPA tests mass loss data reported is represented according to its provenience by country, to visualize its possible influence on mass loss results distribution (top graph), as well as on the dispersion of the respective mass loss differences (bottom graph).

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Figure 2.6 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by country

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To better assess the impact of data provenience on the mass loss differences between the two tests, the average mass loss differences and respective standard deviations were calculated separately for each country and are presented in Table 2.9, along with the respective range of results. The number of tests reported by each country can be consulted in Table 2.3.

Table 2.9 – (PA-CPA) mass loss differences (in mg/dm2) obtained by country Austria Cyprus Greece Hungary Italy Average value Standard Deviation Range (min-max.)

Portugal Poland Slovakia Spain Switzerland

Turkey China

4,1

3,0

2,5

6,1

2,5

5,5

4,8

4,4

2,6

6,6

4,7

3,7

1,7

0,5

2,1

3,6

1,8

3,1

1,0

2,7

3,5

2,7

4,7

2,7

1,6-5,3

2,3-3,5

0-6,8

0,1-25

4-5,9

1,5-12

-1,1-28

2,6-9,6

2,6-13,5 0-8,6

-4,2-26 0,9-9,0

The average values presented in Table 2.9 reveal some relevant variations among the results from the different countries. The results obtained in the inspections carried out at Italy, Spain and Greece, exhibited the lowest average mass loss differences. A common factor among these countries is the significant number of plants working with the cold sealing process. In contrast, the results from Portuguese and Turkish inspections - the two countries with the largest number of tests surveyed - exhibited considerably higher average mass loss differences. All the inspected plants of Portugal work with the hot water sealing process as well as the majority of inspected plants from Turkey. The results reported by countries like Hungary and Switzerland presented the highest average mass loss differences, what may be a consequence of the relative high percentage of tests carried out with test specimens of hollow section type. These findings suggest that there should be multiple factors influencing experimental results. In order to ascertain what kind of factors could specifically affect the PA test results correlation to CPA test results, the two tests mass losses distribution will be further analysed in relation to the type of sealing process, anodic coating thickness class and colour, test specimen’s section type and alloy, and to test solution stirring. However, before proceeding to this extended comparative analysis, a previous examination of the reported mass loss data focused on the extreme values found for the calculated mass loss differences, was done to identify possible erroneous results and outliers that should be discarded.

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2.4.1

Outlying or erroneous results

The histogram displayed in Figure 2.4 indicates the largest values obtained for the mass loss 2

differences - five cases yielding mass loss differences above 18 mg/dm - as possible outliers, since they deviate markedly from the other values obtained in this survey. The statistical Grubb’s test (Annex IV) was used to determine if these results are outliers. This analytical procedure identifies outliers when data presents a normal (or similar) distribution [18]. The Grubb’s test results are presented in the Annex IV and identified all of these five large mass loss differences as outliers with a 1% significance level. This means that the probability of so large differences occurrence by chance should be less than 1%. Outliers should be investigated carefully before considering their elimination from data. It is necessary to determine if they are extreme manifestations of the random variability inherent to the test procedure under investigation and if it is likely that similar values continue to appear, or if they are just erroneous data points. In the case of the largest mass loss differences, it was verified that three of them are referent to tests carried out with specimens cut from hollow profiles (with 25% to 50% of uncoated area) and that in one case the anodic coating was also found to be improper sealed (the CPA test mass loss result was 2

above 30 mg/dm ), what could justify the increased mass loss differences obtained, according to our previous studies. However, data gathered in those previous studies [12][15] indicates that mass loss 2

2

differences rarely overpassed 16 mg/dm and 24 mg/dm , respectively, for proper and improper sealed test specimens. Taking the above in consideration, it was assumed that only the three highest mass loss differences – 2

2

which are all above 20 mg/dm with the correspondent CPA test result below 30 mg/dm – should be eliminated from the population under analysis. In relation to the opposite extreme mass loss differences, those yielding negative (PA-CPA) mass loss differences, they could not be considered outliers according to the Grubb’s test (Annex IV). But they are most likely erroneous mass loss results, especially the three lowest negative ones (those 2

below -2 mg/dm ). It was verified that these results were all reported by the same country and that within this set of results, one was referent to the highest pair of mass loss values reported 2

2

(CPA - 70,4 mg/dm ; PA - 66,8 mg/dm ) and other to a hollow test specimen (with 23% of uncoated area), factors that should originate large positive mass loss differences instead of a negative ones. Then, for these unlikely three extreme values of negative mass loss differences no particular justification was found, unless a possible exchange of the mass loss tests results reported. Therefore, it was decided to discard them. On the other hand, a more significant number of small negative mass loss differences (close to zero) was found (twelve cases). This set of data was carefully analysed and it was verified that this kind of results was mainly reported by two countries (Table 2.9), being mostly obtained for cold sealed tests specimens. Some of them were also associated to a high content of dissolved mass in the CPA test solution what should have the opposite effect on mass loss differences. These factors also

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predominate in the cases of the lowest range of positive mass loss differences (between 0 and 2 2

mg/dm ). In a few of these cases it was referred in the inspector’s report that the test specimens used for the two mass loss tests were cut from adjacent profiles, what then could justify such narrow differences. For the remaining cases no justification or deviation from the standard experimental procedure was found. Nevertheless, due to the significant number of similar cases reported and attending to the reproducibility variance of the two mass loss test methods [12], it was decided to retain this set of negative mass loss differences, considering them as an extreme manifestation of the random variability inherent to the test procedure. On the whole, seven pairs of mass loss tests data were discarded before proceeding to the extended comparative analysis of influencing factors. Figure 2.7 shows the histogram of Figure 2.4 with the discarded points signed by the bars in white. The eliminated points were relative to test specimens of alloys 6060 and 6063, being four of solid profile and three of hollow section, five of them have been hot water sealed and the other two cold sealed, and the respective anodic coating’s thickness belonged either to class 10 µm or to class 15 µm. Thus, due to the elimination of those extreme results from the original data, the set of reported data considered in the following comparative analysis was reduced to 384 pairs of mass loss results. 2

Globally, the average mass loss difference stays practically unchanged: now is 4,0 mg/dm , but the 2

standard deviation was slightly reduced, now being 3,0 mg/dm instead of the previous 3,7 mg/dm

2

(Table 2.8).

Figure 2.7 – Frequency distribution of (PA – CPA) mass loss differences obtained in QUALANOD inspections to anodizing plants with discarded points signed

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2.4.2

Influencing factors on mass loss results

After discarding outlying and erroneous results, the reported data was further analysed in relation to the type of sealing process, anodic coating thickness class and colour, test specimen’s section type and alloy, and to test solution stirring, aiming to evaluate the influence of these factors on the correlation between PA and CPA tests results, hence on mass losses differences distribution. The graphical representation of these correlations is displayed in Figures 2.8 to 2.13. The average mass loss differences and respective standard deviations for each parameter of the listed factors were also calculated and are presented in Tables 2.10 to 2.13. In fact, this comparative analysis evidenced some trends, more patent on the average mass losses values. In spite of the relative high standard deviations often associated to the results, the most influent factors seemed to be the sealing process and test specimen section type. On the contrary, factors like test solution stirring, alloy, anodic coating thickness class and colour did not show any particular influence on mass loss differences distribution or the most likely influent parameters have a number of cases too much reduced to allow significant conclusions. This was the case of the results obtained in the tests carried out with test specimens of black colour (Table 2.11) or of thickness classes of 5 µm (Table 2.10), which yielded the highest average mass loss differences. In relation to the sealing process influence, it could be observed in the graphs of Figure 2.8 that the PA test mass losses obtained with cold sealed test specimens tended to deviate less from the CPA test results and consequently presented lower average mass loss differences (Table 2.10), than those obtained with the other test specimens, especially, with those hot water sealed. This kind of influence has already been suggested by the mass loss differences distribution by country, in which the lowest average mass loss differences were presented by those countries with more results from anodizing plants working with the cold sealing process (Table 2.9). In what concerns section type influence, although data plotted on the graphs of Figure 2.11 indicates a similar range of mass loss differences for both section types, the average mass loss difference is slightly higher in the case of the mass loss tests carried out with test specimens of hollow section (Table 2.12). This should be caused by the additional contribution to the mass loss of bare surfaces aluminium dissolution in the PA test. Figure 2.14 relates the mass loss differences between CPA and PA tests with test specimens’ uncoated area percentage. Generally, the uncoated area of solid section test specimens (cutting edges) represents around 2% to 8% of the total area of the test specimen, and in the case of hollow profiles, it ranged from 10% to 58% of the total area. It is worth mentioning that information concerning total and coated areas was frequently missed in the reports: 55 % of the reports were filled in with the same value for both areas (some of each referred to hollow profiles) or only one value (usually the coated area) was indicated. These cases correspond to “zero” percentage points in the graph of Figure 2.14. For some hollow profiles, an estimative of the percentage of uncoated area was made, based on the respective technical drawing. About 20% of the reports did not mention the section type, these cases were labeled as “unknown” in the plots of Figure 2.11 and 2.14, and in Table 2.12.

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Figure 2.8 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by sealing process

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Figure 2.9 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by anodic coating thickness class

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Figure 2.10 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by anodic coating colour

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Figure 2.11 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test specimens section type

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Figure 2.12 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test specimens alloy

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Figure 2.13 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants identified by test solution stirring

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Table 2.10 – Average (PA-CPA) mass loss differences (mg/dm2) with respect to sealing process and thickness class Sealing process

Average value ± Stand. Dev.

Thickness class

Steam

Hot water

Medium-T

Cold

5 µm

10 µm

15 µm

20 µm

25 µm

3,0±2,2

4,9±3,3

3,6±2,1

2,5±1,9

6,7±5,5

4,1±3,4

3,9±2,5

3,3±2,2

5,2±2,4

Table 2.11 – Average (PA-CPA) mass loss differences (mg/dm2) with respect to anodic coating coloura) Black Average value 7,3±4,4 ± Stand. Dev. a) Only reported during 2014

Bronze

Medium Bronze

Yellow

Inox

Natural

Opaque white

3,2±2,1

3,5±0,8

3,6±0,3

2,0±2,2

3,5±2,3

4,8±4,2

Table 2.12 – Average (PA-CPA) mass loss differences (mg/dm2) with respect to test specimens section and alloy Alloya)

Section Type Solid Average value 3,9±2,7 ± Stand. Dev. a) According to EN 573-3:

Hollow

Unknown

EN AW 6060

EN AW 6063

EN AW 5005

Unknown

5,5±4,0

2,9±2,1

3,9±2,6

4,1±3,3

5,2±1,0

5,9±3,0

Table 2.13 – Average (PA-CPA) mass loss differences (mg/dm2) with respect to test solution stirring

Average value ± Stand. Dev.

Stirred

Not stirred

4,0±3,5

4,9±3,4

The graph of Figure 2.14 shows that the number of high mass loss differences is more significant for the group of test specimens of hollow section, especially for those with more than 20% of uncoated area, what justifies the higher average mass loss evidenced by this group (Table 2.12). However, the fact that similar ranges of mass loss differences were found for test specimens of both section types demonstrates that the presence of uncoated surfaces was not so influent on the PA mass loss test results as expected (considering the range of test specimens’ uncoated areas percentage involved in this survey (0% to 58%)). One possible justification for this finding and also for the lowest mass loss differences found for several hollow test specimens (Figure 2.14), could be the fact that the test specimens are usually taken from the end of profiles, which inside surfaces are also coated, due to the throwing power of the anodizing electrolyte, hence protected against PA test solution chemical attack. 2

On the other hand, for the highest mass loss differences (above 10 mg/dm ) obtained for some solid test specimens, which are of same magnitude of the highest ones found for hollow test specimens, no specific reason was found, being considered extreme manifestations of the inherent random variability of the test method.

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Figure 2.14 – Effect of the percentage of test specimen’s uncoated area on (PA-CPA) mass loss differences

In spite of the more deviating cases found, on the whole, the results of PA and CPA mass loss tests performed within the QUALANOD inspections surveyed during 2013 and 2014, indicate that PA test can be used to replace CPA test in the assessment of anodic coatings sealing quality, preferably with test specimens of solid section, but do not preclude the possibility of applying it also to assess hollow section test specimens, under some circumstances: -

reduced percentage of uncoated area (less than 20% (see Figure 2.14));

-

test specimens cut from the end of profile (as foreseen in ISO 3210 [7]).

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2.5

Impact of PA mass loss test on product inspections results

Like in the previous report [13], the impact of using the PA test for assessing anodic coating sealing quality within QUALANOD inspections surveyed is presented. For this analysis two acceptance limits for the PA test mass loss were considered. The results of the implementation of this test procedure are presented in Table 2.14. All the reported data, comprising 391 pairs of PA and CPA mass loss tests, was considered.

Table 2.14 – Application of PA test, with the acceptance limits of 35 mg/dm2 or 30 mg/dm2, to assess anodic coatings sealing quality within the 2013-2014 QUALANOD inspections Number of negative results

Mass loss criteria

Remarks

CPA > 30 mg/dm2

9

Current situation

PA > 30 mg/dm2

36

More 25 negative results

PA > 35 mg/dm2

16

More 7 negative results

PA > 30 mg/dm2 and CPA > 30 mg/dm2

9

Any of the CPA based negative result passes

PA > 35 mg/dm2 and CPA > 30 mg/dm2

8

One of CPA based negative result passes

Data presented in Table 2.14 demonstrates that if the PA test was used to test assess anodic coating sealing quality in the QUALANOD inspections surveyed, the number of negative results would rise 2

significantly: four times, considering the mass loss acceptance limit of 30,0 mg/dm ; or almost to the 2

double, considering the mass loss acceptance limit of 35,0 mg/dm . It should be noticed that this increase in the number of negative results is equally divided by solid and hollow section test specimens. The CPA test mass losses correspondent to the “extra” negative tests ranged from 2

2

18,6 mg/dm to 29,4 mg/dm (Annex II). In what concerns the acceptance limit for the PA test mass loss, the results resumed in Table 2.14, 2

indicate that only considering the same limit of the CPA test (30,0 mg/dm ) assures that any of the 2

CPA based negative results will pass. If instead of using this lower limit, the limit of 35,0 mg/dm was considered, one of the CPA based negative results would be accepted.

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3|

Analysis of PA and CPA Mass Loss Tests Additional Data from Portuguese QUALANOD’s Inspections (2014 - 2015)

3.1

Influence of production factors on mass loss results dispersion

It is well known that the operating conditions of the anodization process will influence anodic coating properties [1]. Therefore, in order to evaluate a possible effect of operating conditions on the mass loss differences between PA and CPA mass loss tests, during the product inspections carried out since the beginning of 2014, it has been additionally collected data concerning several production parameters: anodization temperature and current density, and sealing time (in min/µm), relative to the test specimens subjected to the mass loss tests. All the collected data is reported in the Annex V (Tables V.1 and V.2). In the graphs of Figure 3.1, the data relating to test specimens (PA-CPA) mass loss differences is plotted against respective production parameters.

Figure 3.1 – (PA-CPA) mass loss differences distribution according to several production parameters - values shown in a box refer to the operating conditions globally recommended by QUALANOD for each parameter

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In the graphs displayed in Figure 3.1 it is possible to see that, within the respective variation ranges, only the anodization current density seems to have some influence on mass loss differences distribution. The respective graph shows a tendency of mass loss differences to increase with decreasing current density. This may be explained by the fact that low current densities imply a slow rate of film formation, hence increased attack on the film, what may cause the softening of the anodic coating at the surface and, consequently, its higher dissolution in the PA test solution.

3.2

Influence of reducing immersion time in the phosphoric acid solution on mass loss differences

From the beginning of 2015, the QUALANOD referee sealing mass loss test is the PA test, instead of the CPA test (Method 2 of ISO 3210 [7]), with an additional modification: the immersion time in the phosphoric acid test solution was reduced from 15 to 13 minutes [14]. The immersion time considered in the QUALANOD product inspection survey carried out during 2013 and 2014 had been the 15 minutes stipulated in the ISO 3210 standard for the CPA test. This reduction of the immersion time was decided to achieve lower mass loss in the PA test solution, hence lower differences between PA and CPA tests results and possibly less dispersion of results. Therefore, aiming to evaluate the consequences of this change in the PA test experimental procedure on mass loss results, in the QUALANOD product inspections that have been carried out since the beginning of 2015, it was decided to continue to perform also the CPA test on test specimens cut from the same profile selected for the PA test. Figure 3.2 presents the correlation between PA and CPA tests mass loss results, obtained in the Portuguese inspections carried out during 2015. A total of 25 pairs of mass loss results were surveyed, corresponding to 22 product inspections. The respective data is also reported in the Annex V (Table V.2). The mass loss data relative to the 2013/2014 inspections was also included in the same graphs for comparison. As expected, the results of the PA mass loss test performed with the reduced immersion time of 13 minutes in the phosphoric acid solution also followed CPA mass loss test response as it was observed for the immersion time of 15 minutes. Likewise, the differences to the CPA test mass losses with the reduced immersion time, plotted on the second graph of Figure 3.2, evidenced also a slight tendency to increase with the CPA mass loss value, although in a way less pronounced. According to the respective trend lines drawn on the first graph of Figure 3.2, the mass losses of the PA test performed with the immersion time of 13 minutes tended to be closer to the CPA test ones than those obtained with the 15 minutes’ immersion time. Globally, the average mass loss difference 2

2

obtained in the 2015’ inspections was 4,0 mg/dm , with a standard deviation of 2,1 mg/dm . These values are lower than the ones obtained in the inspections carried out during 2013-2014, which were 2

2

5,5 mg/dm and 3,1 mg/dm , respectively (Table 2.9).

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Figure 3.2 – PA mass loss test results vs CPA mass loss test results and correspondent mass loss differences obtained in QUALANOD inspections to anodizing plants during 2013/2014 (PA15min) and 2015(PA13min)

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In what concerned results dispersion, performing the PA test with the reduced immersion time led to less extreme mass loss differences between the two test methods: these differences ranged from 2

2

0,5 mg/dm to 9,2 mg/dm (Annex V, Table V.2)), while for the previous immersion time ranged from 2

2

0,1 mg/dm to 25 mg/dm (Table 2.9). Based on the results of this short comparative survey between CPA and PA mass loss tests, it could be assumed that the PA test performed with an immersion time in the phosphoric acid test solution of 13 minutes leads to results closer to those obtained with the CPA test, than with the immersion time of 15 minutes. It should be noticed that this assumption is based on experimental results obtained exclusively with hot water sealed test specimens, which tend to yield larger mass loss differences between the two test methods, as has been observed in the large QUALANOD survey.

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4|

Complimentary studies on PA test

4.1

Influence of PA test solutions temperature on mass loss results

The effect of small variations in the temperature of PA test solutions - nitric acid (predip) and phosphoric acid – on anodic coating’s mass loss results was studied to assess their possible influence on mass loss results dispersion and also to check if these test conditions would require a more tight control for the PA test than for CPA test. The test specimens were cut from aluminium extruded profiles of alloy type 6063, anodized in three different plants, following QUALANOD requirements [6], except when otherwise required to achieve some desired property. These profiles were produced with different anodizing times, sealing processes and sealing times (Table 4.1). On the whole, nine anodic coating types were used in this test program, distributed as indicated in Table 4.1. Due to the long-time elapsed since their production; the CPA test was included to assess current sealing quality of some of the anodic coating types (one test specimen each). The several PA tests involved in this test program were carried out with duplicate test specimens of each anodic coating type. Table 4.1 – Test specimens thickness classes required and other production parameters by anodic coating type and their distribution according to the Test program Anodic Coating

Colour

Anodizing temperature

Process

15 µm

21 °C

Hot water

BC Bronze BM FC natural

15 µm

18 °C

15 µm

B

20 µm

Time

CPA test

PA test with ∆Tpredip

PA test with ∆Tpa

5 min/µm



-



0,6 min/µm



-



0,8 min/µm



-



0,4 min/µm



Cold

FM A

Test program

Sealing

Thickness class

18 °C









-



-

-



-

-



-



-



3 min/µm C

natural

Hot water

25 µm

D

20 µm

25 °C

F

15 µm

18 °C

1 min/µm

The CPA test was performed according to Method 2 of ISO 3210 [7]. The PA tests were carried out following the CPA test experimental procedure with the modifications introduced by QUALANOD Update Sheet nº20 [14], with different test solutions (predip and phosphoric acid) temperatures, as indicated in Table 4.2.

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Table 4.2 –Test solutions temperature and immersion time used in the Test program

Composition

Temperature

Composition

Temperature

Immersion time in pa solution

Nitric acid (470 ± 15) g/l

19,1°C

35 ml phosphoric acid + 20 g chromium (IV) oxide (per litre)

37,7°C

15 min

Predip solution

Phosphoric acid (pa) solution

Test Method

CPA test PA test with ∆Tpredip PA test with ∆Tpa

Nitric acid (470 ± 15) g/l

15,5°C; 19,3°C; 25,1°C 19,1°C

35 ml phosphoric acid (per litre)

37,6ºC – 37,9ºC 13 min 35,9°C; 37,8°C; 39,8°C

The predip immersion step of the PA test follows ISO 3210 standard procedure that stipulates a temperature of 19°C±1°C for this acid solution, during the 10 minutes of immersion. This range of temperatures can easily be found inside a laboratory with air conditioned. However, not all the anodizing plants laboratories have air conditioned. Thus, the immersion in the predip solution which is usually carried out at room temperature, may be carried out at temperatures that may fall outside the specified range. Therefore, the predip solution temperatures selected for this test program (Table 4.2), intended to represent extreme conditions that, according to experience, could be found in plant’s laboratories along the year. In what concerns the phosphoric acid solution, it is required that its temperature should be strictly kept within the range of 38°C±1°C [7][14]. The control of this temperature is usually carried out by placing the vessel with the test solution inside a thermostatic bath or over a hot plate. This last one is more subject to temperature variations and to temperature gradients establishment, if the solution is not properly stirred. Therefore, the range of phosphoric acid solution temperatures selected for this test program (Table 4.2), aimed to evaluated how far little changes in this temperature may affect PA test mass losses and could contribute for the large dispersion found for the mass loss differences between PA and CPA tests. All the results obtained in this test program are reported in the Annex VI, including those of CPA test, which pointed out only the FM coating type as improper sealed (the CPA mass loss was above 2

30 mg/dm ). The graphs displayed in Figures 4.1 to 4.2 present the experimental data obtained, relating the PA test mass losses with the temperature of the predip (Figure 4.1) or of the phosphoric acid (Figure 4.2) test solutions.

4.1.1

Effect of the nitric acid (predip) solution temperature variation

In relation to the effect of predip solution temperature on PA test mass loss results, as it can be seen on the graph of Figure 4.1, the results obtained are somewhat contradictory: test specimens of anodic coating types A and B showed a constant rise of the mass loss with predip solution temperature -2

-1

increase, although at a very low rate (maximum: 0,14 mg.dm .°C (Annex VI, Table VI.1)), while the test specimens of anodic coating types C and D showed a slight decrease in the mass loss within the same temperature range. Therefore, on the whole, the results suggest that predip solution

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temperature variations should have very little influence on PA test mass loss results, at least for proper sealed anodic coatings.

Figure 4.1 – PA mass loss test results for different predip solution temperatures

4.1.2

Effect of the phosphoric acid solution temperature variation

In relation to the effect of phosphoric acid solution temperature on PA test mass loss, as it can be seen on the graph of Figure 4.2, the results obtained evidenced a generalised increase in the PA test mass loss with increasing phosphoric acid temperature. The rate of this variation ranged from -2

0,2 mg.dm .°C

-1

-2

to 1,4 mg.dm .°C

-1

(Annex VI, Table VI.2), being the highest value relative to the -2

-1

improper sealed anodic coating type FM. In average it was 0,7 mg.dm .°C . Therefore, the 2°C variation of the phosphoric acid temperature allowed in the standard procedure, 2

may causes a variation in the mass loss of around 1,4 mg/dm , what is close to the inherent global repeatability standard deviation of the PA test method and similar to that of CPA test, as determined in 2

2

the last QUALANOD Inter-laboratory test, that were 1,8 mg/dm and 1,4 mg/dm , respectively, for the same range of mass losses [12]. The relation between the average (PA-CPA) mass loss differences of the several anodic coating types and the CPA mass loss was plotted in the graph of Figure 4.3 for the three temperatures tested. As expected, the differences between the two test methods results tend to increase with temperature. 2

For the lower temperature (∼36°C), in average, the mass loss difference was 0,9 mg/dm while for the 2

higher temperature (∼40°C) it was 3,6 mg/dm (Annex VI). However, within the same temperature, the dispersion of the mass loss differences results is similar for the three temperatures.

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Figure 4.2 – Average PA mass loss test results and respective standard deviation for different phosphoric acid solution temperatures

Figure 4.3 – Average (PA-CPA) mass loss differences vs CPA mass losses of the several anodic coating types for different phosphoric acid solution temperatures

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These findings suggest that the variation of phosphoric acid solution temperature may contribute, in lesser extent, to the mass loss results dispersion. However, this effect should only become significant if the solution temperature varies outside the standard limits. Within the standard limits, the mass loss differences dispersion should be more associated with anodic coating intrinsic characteristics: as in the large QUALANOD survey, considering only the proper sealed types, it was observed that the cold sealed (FC) anodic coating type tends to yield lower mass loss differences, while the coloured ones (BM), in general, yielded the largest differences (Figure 4.3, Table VI.3).

4.2

Aluminium alloy dissolution in the PA test solutions

One of the questions raised during the revision works of the ISO 3210 standard that are being done under the ISO/TC 79/SC 2/WG 15 committee responsibility, in order to include also the PA test, is the maximum allowable dissolution of the uncoated metallic substrate in the predip and phosphoric acid 2

solutions. This limit was found to be 8 mg/dm for the alloy EN AW-6063, for an immersion time in the phosphoric acid solution of 15 minutes [13]. However, the immersion time in the phosphoric acid solution of the PA test experimental procedure currently proposed is 13 minutes instead of the former 15 minutes. Therefore, in order to better define a possible mass loss limit for the substrate mass loss, it is important to know the effect of this reduced immersion time on the substrate dissolution, not only for the previous tested alloy, but also for other types of alloys also used in anodizing plants. Taking the above aspects in consideration, it was decide to carry out a new set of dissolution tests with the two aluminium alloys available at LNEC (Table 4.3). In this new test program, the mass loss of uncoated test specimens of those two aluminium alloys was determined following the PA test experimental procedure currently used, which involved the following immersion steps [7][14]: first the immersion in a 50% nitric acid solution (predip), at 19ºC, for ten minutes, then the immersion in the phosphoric acid solution, at (38±1)ºC, for 13 minutes. Table 4.3 – Aluminium alloys composition (in %)1 according to EN 573-3 [19] Silicon

Iron

Coper

Manganese

Magnesium

Chromium

Zinc

Titanium

Other

Aluminium

EN AW-5005

0,30

0,7

0,20

0,20

0,50-1,1

0,10

0,25

-

0.15

remainder

EN AW-6063

0,20-0,6

0,35

0,10

0,10

0,45-0,9

0,10

0,10

0,10

0,15

remainder

1

The contents indicated are maximum limits or limited ranges.

The aluminium alloy test specimens were cut from 1,1 mm thick sheets, with dimensions 2

corresponding to an exposed area of approximately 1 dm . Four and six replicates were tested, respectively, for alloy EN AW-6063 and EN AW-5005. The respective individual mass loss results are

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presented in the Annex VI (Table VI.3). The average mass losses and respective standard deviations obtained for each one of the two alloys tested are indicated in the Table 4.4. Table 4.4 – Aluminium alloys mass loss in the PA test Average mass loss (mg/dm2)

Standard deviation (mg/dm2)

EN AW-5005

9,3

±0,2

EN AW-6063

5,0

±0,2

The results of the dissolution tests shown in Table 4.4 evidenced that alloy 5005 test specimens suffered higher dissolution than the 6063 alloy test specimens, probably due to their higher contents in alloying elements like copper and iron (Table 4.3). The mass loss now obtained for the EN AW-6063 test specimens is slightly lower than the one obtained in previous tests, carried out with the test specimens of the same alloy type, which yielded an 2

global average mass loss of 7,1±0,7 mg/dm [13]. This reduction in the mass loss is justified by the reduction of the immersion time in the phosphoric acid solution now used, although the current mass 2

loss values are lower than it was expected, considering the variation rate of 0,52 mg/dm per minute of immersion, determined in the set of tests carried out in those previous studies [13]. Besides the reduction in the immersion time in the phosphoric acid solution, the other difference in the experimental procedure used in the two sets of dissolution tests carried out with test specimens of alloy EN AW-6063, is that in the previous study, the immersion step sequence was interrupted to allow 2

measurement of the mass loss also in the predip solution, what was in average 0,7 mg/dm (results not presented in the previous report). The fact that in those previous experiments the anodic layer of the test specimens was completely dry when they were immersed in the phosphoric acid solution may have led to an higher chemical attack of the anodic coating, than when they were immersed wet (soaked in water), as stipulated in the standard procedure and followed in the current set of tests.

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5|

Conclusions

The analysis of the data relative to the PA and CPA mass loss tests carried out within the QUALANOD inspections, during 2013 and 2014, showed the following: •

CPA and PA mass loss test methods evidenced similar trends: the PA test follows CPA test response. However, the two test methods led to statistically significant different mass loss results. As expected, the PA test tended to yield larger mass loss values than the CPA test;

The differences between the mass loss results of the two test methods ranged from 2

2

(-4,2) mg/dm to 28,4 mg/dm . These differences tended to increase with the mass loss value. 2

However, 91% of them are positive and less than 10 mg/dm ; •

Globally, the average mass loss difference found for the 391 pairs of mass loss tests surveyed 2

2

was 4,2 mg/dm with a standard deviation of 3,7 mg/dm . Discarding some of the most extreme results obtained, those with a probability of occurrence lower than 1%, the average 2

2

mass loss difference was 4,0 mg/dm with a standard deviation of 3,0 mg/dm ; •

Additionally, the comparative analysis done to the two mass loss tests results evidenced some trends: o

PA test mass losses obtained with cold sealed test specimens tended to deviate less from the CPA test results than with the other types of sealed specimens, in particular, hot water sealed ones;

o

The average mass loss difference was slightly higher for test specimens of hollow section. However, the presence of uncoated surfaces was not as influential on the PA as expected. Possibly due to some kind of passivation occurred in the anodizing process, only test specimens with more than 20% of uncoated area showed more significant higher mass loss differences;

o

Factors like test solution stirring, alloy, anodic coating thickness class and colour did not show any particular influence on mass loss differences;

If the PA test had been used, instead of the CPA test, to assess anodic coating sealing quality in the QUALANOD inspections survey, the number of negative results based on high mass loss results would have been significantly higher: four times, considering the acceptance limit 2

2

of 30,0 mg/dm . If instead of using this last limit, the limit of 35,0 mg/dm had been used, the number of negative results would have risen only to almost the double. However, it should be noticed that with this last limit, one CPA based negative inspection would have passed, what turned the higher acceptance mass loss limit unappropriated.

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The analysis of the additional data relative to the PA and CPA mass loss tests carried out within the Portuguese QUALANOD inspections since 2014, showed the following: •

The effect of anodizing operating conditions on the mass loss differences between PA and CPA tests only revealed to be significant for the current density: in average, the mass loss differences between the two methods increased when anodizing current density decreased;

The reduction of the immersion time in the phosphoric acid test solution from 15 to 13 minutes led to PA test results still higher, but closer to the CPA test results than it had been obtained for the immersion time of 15 minutes.

The results obtained in the complimentary studies on PA test carried out, showed the following: •

The predip solution temperature variation from 15ºC to 25ºC have very little influence on the PA mass loss test results, at least for proper sealed anodic coatings;

The variation of phosphoric acid solution temperature of ±1ºC permitted in the test method specification may contribute, in lesser extent, to the mass loss differences between the two test methods dispersion, since mass loss increased with this solution temperature;

2

The alloy EN AW-5005 yielded a higher mass loss (9,3 mg/dm ) in the PA test than the alloy 2

EN AW-6063 (5,0 mg/dm ).

On the whole, based on the comparative analysis of the results of PA and CPA mass loss tests performed herein, it can be concluded that the PA mass loss test can replace the CPA mass loss test for the assessment of anodic coatings sealing quality, following the experimental procedure of the CPA test except in what refers to the immersion time in the phosphoric acid test solution, which should be reduced to 13 minutes. The PA mass loss test, in principle, shall be preferably performed with test specimens of solid section. However, data obtained do not preclude the possibility of applying this test also to assess hollow section test specimens. The circumstances for this possibility could be: -

reduced percentage of uncoated area (less than 20% (see Figure 2.14));

-

test specimens cut from the end of profile (as foreseen in ISO 3210 [7]).

In what concerns the acceptance limit for the PA test mass loss, due to the somewhat random large 2

range of mass loss differences, only considering the same limit of the CPA test (30,0 mg/dm ) assures at least the same quality level of the CPA test. However, the results also show that, the control of sealing quality by the PA test, in practice, will probably impose a tighter in-house control of sealing baths working conditions to anodizing plants, targeted to achieve lower mass loss results than before (when CPA test was the reference test). This change will probably be more significant for the anodizing plants working with the hot water sealing process.

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Lisbon, LNEC, December of 2015

APPROVED

AUTHORS

Head of Metallic Materials Unit

Elsa Vaz Pereira

Isabel Rute Fontinha Assistant Researcher

Head of Materials Department

Arlindo Gonรงalves

Nuno Garcia Senior Technician

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References

[1]

[2] [3]

[4] [5]

[6] [7]

[8]

[9]

[10]

[11] [12] [13]

[14]

[15]

[16]

[17]

[18]

38

S. Wernick, R. Pinner, P. G. Sheasby. The surface treatment and finishing of aluminium and its alloys., Vol.2, 5th Ed., ASM International, Finishing Publications Ltd, Redwood Books, Great Britain, 1987. I. R. Fontinha; M. M. Salta. Influence of sealing process on corrosion behaviour of anodized aluminium. EUROCORR2005, Lisbon, 4-8 September, 2005. M.J. Bartolomé , J.F. del Río, E. Escudero, S. Feliu Jr., V. López, E. Otero, J.A. González. Behaviour of different bare and anodised aluminium alloys in the atmosphere. Surface & Coatings Technology 202, 2783–2793. 2008. Robin Furneaux. Replacement for the chromic / phosphoric weight loss test. Stage 1 – review of the technical literature. Report TSR10-2, TSR, UK. 2010. ISO DTR 16689 – Anodizing of aluminium and its alloys – Phosphoric acid chromic acid immersion test – Evaluation of candidates to replace it. ISO/TC 79/SC 2 N 680, ISO, 2011. Specifications for the QUALANOD Quality Label for Sulphuric Acid-Based Anodizing of Aluminium. Ed.01.07.2010. EURAS/EWWA - QUALANOD, Zurich. 2010. ISO 3210 – Anodizing of aluminium and its alloys — Assessment of quality of sealed anodic oxidation coatings by measurement of the loss of mass after immersion in phosphoric acid/chromic acid solution, ISO, Genéve. 2010. Simon Meirsschaut. Message from ESTAL Technical Coordinator. 2014. Available at http://www.estal.org/sites/default/files/ESTAL%20important%20issues%20Jan%202014_0.p df M. Manuela Salta, I. R. Fontinha. Study on anodic oxide coating sealing quality assessment methods for phosphoric/chromic acid immersion standard test replacement – Proposal for a new test specification. Report nº 342/2011-NMM, LNEC, December, 2011 I. R. Fontinha, M. Manuela Salta. Study of a new test method for anodic oxide coating sealing quality assessment to replace the phosphoric/chromic acid immersion test Application to cold sealed anodic coatings. Report nº 49/2012-DM/NMM, LNEC, March, 2012 M. Manuela Salta, I. R. Fontinha, N. Garcia. 2011 Inter-laboratory test of anodized aluminium testing methods, Report nº 341/2011-NMM, LNEC, November, 2011. I. R. Fontinha, N. Garcia, M. Manuela Salta. 2013 QUALANOD Round Robin Test on anodized aluminium testing methods. Report nº 312/2013-NMM, LNEC, October, 2013 I. R. Fontinha, N. Garcia, M. Manuela Salta. Analysis of the new chromium-free test method results from QUALANOD inspections to anodizing plants in 2013. Report nº 313/2013-NMM, LNEC, October, 2013. UPDATE SHEET Nº 20 of QUALANOD Specifications Ed. 01.07.2010. 2.3.3 Measurement of loss of mass after immersion in phosphoric acid solution with prior acid treatment (mass loss test). 12.06.14 (Modified may 2015). I. R. Fontinha, M. Manuela Salta. Studies on the new chromium-free phosphoric acid immersion test method for anodic oxide coating sealing quality assessment by mass loss. Report nº 314/2013-NMM, LNEC, October. 2013 ISO/TC 79/SC 2 N 735 – Draft minutes of the 28th meeting of ISO/TC 79/SC 2 Light metals and their alloys/Organic and anodic oxidation coatings on aluminium. ISO, November, 2012. ISO/DIS 3210 - Anodizing of aluminium and its alloys - Assessment of quality of sealed anodic oxidation coatings by measurement of the loss of mass after immersion in acid solution(s). ISO/TC 79/SC 2 N765. JISC. Tokyo. 2015. ASTM E178 – 08 - Standard Practice for Dealing with Outlying Observations. ASM International. 2008. LNEC - Proc. 0204/121/20079


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[19] EN 573-3 - Aluminium and aluminium alloys - Chemical composition and form of wrought products - Part 3: Chemical composition and form of products. CEN, Brussels. 2013. [20] N. L. Sukiman, X. Zhou, N. Birbilis, A.E. Hughes, J. M. C. Mol, S. J. Garcia, X. Zhou, G. E. Thompson. Chapter 2 - Durability and Corrosion of Aluminium and Its Alloys: Overview, Property Space, Techniques and Developments. InTech. Open acess. http://dx.doi.org/10.5772/53752 [21] Fundamentals of Statistics. Grubb’s Outlier Test and critical values. Available at http://www.statistics4u.com/fundstat_eng/ee_grubbs_outliertest.html

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Annexes

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ANNEX I Forms of the inspection reports

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2013 Inspector’s reporting sheet - RS09_procedure for inspectors 27.11.12

* ISO 3210:2010 states that the test solution should not be used after more than 4,5 g of anodic coating have been dissolved per litre of solution; of course, the chromic/phosphoric acid solution does not dissolve aluminium metal. We do not know how this criterion could be applied to the new phosphoric acid test where both anodic coating and aluminium metal might be dissolved. As an approximation, the total mass dissolved is the sum of the mass losses from previous tests carried out with the solution.

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2014 Inspector’s reporting sheet - RS01_procedure for inspectors version 2. 21.01.14

1

ISO 3210:2010 states that the test solution should not be used after more than 4,5 g of anodic coating have been dissolved per litre of solution; of course, the chromic/phosphoric acid solution does not dissolve aluminium metal. We do not know how this criterion could be applied to the new phosphoric acid test where both anodic coating and aluminium metal might be dissolved. As an approximation, the total mass dissolved is the sum of the mass losses from previous tests carried out with the solution. Note: report this value in the units “mass per litre” 2

Examples of cross section type: hollow

; solid

Note: The highlighted text refers to the additional data requested in 2014.

46

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ANNEX II Results from QUALANOD’s Product Inspections Survey (2013-2014)

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Licence

1624 1624 1629 1411 1411 1615 1503 1610 1630 1633 1604 1613 1614 1631 1406 1406 1413 1413 1414 1414 1038 1505 1635 1412 1412 1612 1415 1415 1634 1046 1405 1405 1406 1406 1406 1406 1610 1626 1625 400 400 401 401

Date

12-12-2012 13-12-2012 29-01-2013 05-02-2013 05-02-2013 07-02-2013 13-02-2013 13-02-2013 13-02-2013 14-02-2013 20-02-2013 20-02-2013 21-02-2013 21-02-2013 05-03-2013 05-03-2013 06-03-2013 06-03-2013 07-03-2013 07-03-2013 13-03-2013 14-03-2013 14-03-2013 19-03-2013 19-03-2013 19-03-2013 20-03-2013 20-03-2013 20-03-2013 21-03-2013 21-03-2013 21-03-2013 26-03-2013 26-03-2013 26-03-2013 26-03-2013 27-03-2013 28-03-2013 04-04-2013 09-04-2013 09-04-2013 10-04-2013 10-04-2013

CPA Total area 1,799 0,841 0,667 0,655 0,557 0,618 2,025 0,833 0,535 0,940 0,840 1,725 0,498 0,830 0,895 0,895 0,698 0,721 0,818 0,811 1,646 1,275 2,180 0,756 0,766 0,296 0,764 0,762 0,957 0,570 0,736 0,786 0,752 0,736 0,829 0,815 0,963 0,372 0,845 0,854 0,834 1,230 1,249

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 1,799 30 Y 0,0 16,68 1,853 1,853 46,5 Y 0,841 14 Y 0,0 16,65 0,843 0,843 16,4 Y 0,667 7,6 Y 0,0 11,39 0,525 0,525 9,2 Y 0,616 6,9 Y 6,0 11,20 0,639 0,600 9,8 Y 0,518 6,5 Y 7,0 12,55 0,662 0,623 12,3 Y 0,618 14,5 Y 0,0 23,47 0,652 0,652 20,7 Y 2,025 11,8 N 0,0 5,83 2,025 2,025 12,64 N 0,833 16,1 Y 0,0 19,33 0,845 0,845 18,3 Y 0,535 6,8 Y 0,0 12,71 0,602 0,602 6,9 Y 0,940 14,72 Y 0,0 15,67 0,940 0,940 15,79 Y 0,840 15,8 Y 0,0 18,81 0,860 0,860 38,8 Y 1,725 25,4 Y 0,0 14,72 1,312 1,312 33 Y 0,498 4 Y 0,0 8,03 0,549 0,549 6,8 Y 0,830 22,9 Y 0,0 27,59 0,790 0,790 23,6 Y 0,876 24,2 Y 2,1 27,63 0,919 0,900 28,1 Y 0,876 29,7 Y 2,1 33,90 0,902 0,883 38,4 Y 0,683 11,5 Y 2,1 16,84 0,675 0,660 13,8 Y 0,707 13,3 Y 1,9 18,81 0,692 0,677 15,8 Y 0,804 6 Y 1,7 7,46 0,809 0,796 9,7 Y 0,797 7,6 Y 1,7 9,54 0,820 0,807 10,5 Y 1,646 16 Y 0,0 9,72 1,646 1,646 18,8 Y 1,275 12,16 Y 0,0 9,54 1,295 1,295 14,75 Y 2,180 43,5 Y 0,0 19,95 2,180 2,180 87,3 Y 0,741 7,3 Y 2,0 9,85 0,759 0,743 9,2 Y 0,750 7,8 Y 2,1 10,40 0,754 0,738 10,6 Y 0,296 5,5 Y 0,0 18,56 0,364 0,364 9 Y 0,745 7,9 Y 2,5 10,60 0,764 0,744 9,9 Y 0,742 8,8 Y 2,6 11,86 0,766 0,746 8,9 Y 0,448 10,9 Y 53,2 24,33 1,023 0,493 17 Y 0,502 8,4 Y 12,0 16,75 0,570 0,502 9,5 Y 0,698 12,1 Y 5,2 17,34 0,684 0,646 14,7 Y 0,748 13,1 Y 4,8 17,51 0,690 0,652 14 Y 0,733 6,4 Y 2,5 8,73 0,744 0,725 11,3 Y 0,717 6,4 Y 2,6 8,93 0,728 0,709 11,6 Y 0,793 15,3 Y 4,3 19,29 0,792 0,756 20,9 Y 0,779 16,1 Y 4,4 20,67 0,810 0,774 21,6 Y 0,963 22,7 Y 0,0 23,57 0,803 0,803 20,9 Y 0,372 9,2 Y 0,0 24,73 0,278 0,278 6,8 Y 0,845 15 Y 0,0 17,75 0,845 0,845 20 Y 0,846 6,5 N 0,9 7,68 0,862 0,854 8,3 N 0,827 6,5 N 0,9 7,86 0,834 0,827 7,8 N 0,889 15,1 N 27,7 16,99 1,220 0,882 18,3 N 0,903 17,4 N 27,7 19,27 1,192 0,861 19,9 N

LNEC - Proc. 0204/121/20079

PA % PA Mass loss uncoated (mg/dm2) area 0,0 25,10 0,0 19,45 0,0 17,52 6,1 16,33 5,9 19,74 0,0 31,77 0,0 6,24 0,0 21,66 0,0 11,46 0,0 16,81 0,0 45,12 0,0 25,15 0,0 12,39 0,0 29,87 2,1 31,22 2,1 43,49 2,2 20,91 2,2 23,34 1,6 12,19 1,6 13,01 0,0 11,42 0,0 11,39 0,0 40,05 2,1 12,38 2,1 14,36 0,0 24,73 2,6 13,31 2,6 11,93 51,8 34,48 12,0 18,94 5,6 22,76 5,5 21,47 2,6 15,59 2,6 16,36 4,5 27,65 4,4 27,91 0,0 26,04 0,0 24,46 0,0 23,67 0,9 9,72 0,9 9,43 27,7 20,75 27,7 23,11

PA-CPA

8,42 2,79 6,13 5,13 7,19 8,30 0,41 2,33 -1,25 1,14 26,31 10,43 4,36 2,28 3,60 9,58 4,07 4,53 4,72 3,48 1,70 1,85 20,09 2,53 3,96 6,17 2,70 0,07 10,15 2,19 5,42 3,96 6,85 7,43 8,35 7,24 2,47 -0,27 5,92 2,04 1,57 3,76 3,84

Section

Sealing process

Thickness Class

Alloy

U U U S S H S S S H S S S S S S S S S S S S H S S H S S H H S S S S S S S S S S S H H

HW HW C HW HW HW C HW HW C HW HW HW HW HW HW HW HW HW HW C C C HW HW HW HW HW HW C HW HW HW HW HW HW HW HW HW MT MT HW HW

10 10 10 15 15 10 10 15 10 10 10 10 10 5 25 25 15 15 15 15 15 15 10 15 15 10 20 20 10 15 15 15 15 15 15 15 10 10 10 10 10 15 15

AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6060 AA 6060

Colour

Thickness

49


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

743 1039 1600 1048 1632 1700 1700 1700 1700 1045 1614 1618 1621 1626 1623 1613 1004 1014 1617 1627 1049 736 1605 1619 300 1632 1025 1506 715 1607 1412 1412 1012 1018 1415 1415 1029 1047 1213 1406 1406 1202

50

Date

10-04-2013 10-04-2013 10-04-2013 11-04-2013 11-04-2013 17-04-2013 17-04-2013 17-04-2013 17-04-2013 18-04-2013 24-04-2013 25-04-2013 25-04-2013 02-05-2013 06-05-2013 07-05-2013 08-05-2013 08-05-2013 08-05-2013 08-05-2013 14-05-2013 16-05-2013 20-05-2013 21-05-2013 22-05-2013 22-05-2013 23-05-2013 24-05-2013 27-05-2013 27-05-2013 28-05-2013 28-05-2013 29-05-2013 29-05-2013 29-05-2013 29-05-2013 30-05-2013 30-05-2013 30-05-2013 30-05-2013 30-05-2013 12-06-2013

CPA Total area 0,300 0,480 0,599 0,406 0,580 1,849 2,694 2,694 1,849 0,980 0,411 0,985 0,369 0,517 0,767 0,835 0,990 1,800 0,740 1,380 1,150 0,350 1,395 0,940 1,350 0,864 1,600 1,046 0,250 1,233 0,713 0,749 1,610 1,590 0,754 0,744 1,130 1,160 1,020 0,639 0,632 0,890

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 0,300 Y 0,0 10,20 0,300 0,300 Y 0,426 10,6 Y 11,2 24,88 0,480 0,426 22,7 Y 0,599 10,1 Y 0,0 16,88 0,599 0,599 12,8 Y 0,406 7,8 Y 0,0 19,21 0,406 0,406 7,6 Y 0,580 15,2 Y 0,0 26,22 0,580 0,580 17,1 Y 1,053 16,8 N 43,1 15,95 1,821 1,037 30,5 N 1,382 22,6 N 48,7 16,35 2,694 1,382 35,7 N 1,382 22,8 N 48,7 16,49 2,694 1,382 35,5 N 1,053 21,7 N 43,1 20,61 1,849 1,053 29 N 0,980 11,2 Y 0,0 11,43 0,980 0,980 15,3 Y 0,411 4,7 Y 0,0 11,45 0,557 0,557 9,4 Y 0,985 15,6 Y 0,0 15,84 1,044 1,044 20,7 Y 0,369 8,5 Y 0,0 23,02 0,339 0,339 9,3 Y 0,517 5,4 Y 0,0 10,45 0,482 0,482 7 Y 0,767 8,1 Y 0,0 10,56 0,767 0,767 9,1 Y 0,835 18,7 Y 0,0 22,40 0,773 0,773 21,3 Y 0,990 1,4 Y 0,0 1,41 0,990 0,990 2,9 Y 1,800 23,9 Y 0,0 13,28 1,800 1,800 31,2 Y 0,740 16,9 Y 0,0 22,84 0,740 0,740 18,9 Y 1,380 19,9 Y 0,0 14,42 0,920 0,920 16,1 Y 1,150 22,3 Y 0,0 19,39 1,150 1,150 29,6 Y 0,350 Y 0,0 11,60 0,350 0,350 Y 1,395 29,5 Y 0,0 21,15 1,395 1,395 28,2 Y 0,940 17,1 Y 0,0 18,19 0,940 0,940 19,2 Y 1,350 10,5 Y 0,0 7,78 1,350 1,350 14,8 Y 0,864 21 Y 0,0 24,31 0,832 0,832 22 Y 1,600 12,2 Y 0,0 7,63 1,600 1,600 14,6 Y 1,046 21,98 Y 0,0 21,01 1,038 1,038 27,98 Y 0,250 Y 0,0 10,33 0,250 0,250 Y 1,233 27 Y 0,0 21,89 1,212 1,212 26,7 Y 0,669 5,8 Y 6,2 8,67 0,717 0,673 9,6 Y 0,705 6,7 Y 5,9 9,50 0,677 0,663 9,4 Y 1,610 14,3 Y 0,0 8,88 1,610 1,610 15,4 Y 1,590 16,2 Y 0,0 10,19 1,590 1,590 16,3 Y 0,730 8,2 Y 3,2 11,23 0,736 0,712 12,2 Y 0,720 10,3 Y 3,2 14,31 0,720 0,696 13,1 Y 1,130 15,3 Y 0,0 13,54 1,130 1,130 23,7 Y 1,160 14,6 Y 0,0 12,59 1,160 1,160 17,9 Y 1,000 11,9 Y 2,0 11,90 1,020 1,000 14,5 Y 0,628 6,5 Y 1,7 10,35 0,648 0,637 9,6 Y 0,621 6,8 Y 1,7 10,95 0,635 0,624 10,5 Y 0,850 17,1 Y 4,5 20,12 0,890 0,850 25,1 Y

PA % PA Mass loss uncoated (mg/dm2) area 0,0 13,10 11,2 53,29 0,0 21,39 0,0 18,72 0,0 29,50 43,1 29,42 48,7 25,82 48,7 25,68 43,1 27,54 0,0 15,61 0,0 16,87 0,0 19,83 0,0 27,43 0,0 14,51 0,0 11,86 0,0 27,55 0,0 2,93 0,0 17,33 0,0 25,54 0,0 17,50 0,0 25,74 0,0 15,40 0,0 20,22 0,0 20,43 0,0 10,96 0,0 26,44 0,0 9,13 0,0 26,96 0,0 12,72 0,0 22,02 6,1 14,26 2,1 14,18 0,0 9,57 0,0 10,25 3,3 17,13 3,3 18,82 0,0 20,97 0,0 15,43 2,0 14,50 1,7 15,07 1,7 16,83 4,5 29,53

PA-CPA

2,90 28,40 4,51 -0,49 3,28 13,46 9,48 9,19 6,93 4,18 5,42 3,99 4,42 4,06 1,30 5,16 1,52 4,06 2,70 3,08 6,35 3,80 -0,93 2,23 3,19 2,14 1,50 5,94 2,39 0,13 5,59 4,67 0,68 0,06 5,90 4,52 7,43 2,84 2,60 4,72 5,88 9,41

Section

Sealing process

Thickness Class

Alloy

U S S S H H H H H H H S S S S H S S S S S U H S S S S S U H S S S S S S S S S S S S

HW C HW C HW HW HW HW HW C HW C HW HW HW HW S C C HW HW C HW HW HW HW HW C HW HW HW HW C C HW HW C C HW HW HW HW

10 15 10 5 10 10 10 10 10 10 10 10 15 10 10 10 15 15 10 10 15 20 10 10 15 10 15 10 25 10 15 15 15 15 25 25 15 10 15 15 15 15

AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 Unknow AA 6063 AA 6063 Unknow

Colour

Thickness

LNEC - Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

1050 1204 1608 1602 1620 1207 1609 1619 1414 1414 1414 1414 1413 1413 1405 1405 1630 1633 1610 1629 1635 1634 1605 1615 1623 1618 1621 1631 1614 1043 1624 741 1041 1619 1042 1632 743 1506 719 1045 728 1503

Date

13-06-2013 13-06-2013 17-06-2013 18-06-2013 19-06-2013 25-06-2013 26-06-2013 26-06-2013 02-07-2013 02-07-2013 02-07-2013 02-07-2013 03-07-2013 03-07-2013 04-07-2013 04-07-2013 16-07-2013 18-07-2013 19-07-2013 25-07-2013 26-07-2013 26-08-2013 27-08-2013 29-08-2013 09-09-2013 10-09-2013 11-09-2013 11-09-2013 12-09-2013 19-09-2013 24-09-2013 25-09-2013 25-09-2013 25-09-2013 26-09-2013 27-09-2013 02-10-2013 02-10-2013 03-10-2013 03-10-2013 04-10-2013 04-10-2013

CPA Total area 2,470 0,780 0,662 0,750 0,635 1,000 0,754 0,811 0,976 0,939 0,966 0,961 0,638 0,645 1,172 1,173 0,324 0,675 0,740 0,800 0,535 2,214 0,919 0,422 0,888 0,799 0,358 0,710 0,961 1,064 1,126 1,330 1,390 0,500 0,958 1,250 0,980 1,054 1,050 0,980 0,850 0,588

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 2,470 8,6 Y 0,0 3,48 2,470 2,470 10,5 Y 0,760 13,8 Y 2,6 18,16 0,780 0,760 19,7 Y 0,662 12,6 Y 0,0 19,05 0,680 0,680 14,5 Y 0,750 1,7 Y 0,0 2,27 0,830 0,830 1,4 Y 0,635 17,4 Y 0,0 27,42 0,620 0,620 20,6 Y 0,970 30 Y 3,0 30,93 1,000 0,970 39 Y 0,754 11,5 Y 0,0 15,26 0,754 0,754 14,1 Y 0,811 16,1 Y 0,0 19,85 0,876 0,876 19,4 Y 0,929 12,6 Y 4,8 13,56 0,949 0,902 17 Y 0,877 12,4 Y 6,6 14,14 0,967 0,905 19,5 Y 0,919 13 Y 4,9 14,15 0,950 0,903 18,1 Y 0,899 17,2 Y 6,5 19,13 0,985 0,923 25,7 Y 0,620 9,8 Y 2,8 15,81 0,700 0,682 14,2 Y 0,627 10,3 Y 2,8 16,43 0,625 0,607 13,2 Y 0,547 10,8 Y 53,3 19,74 1,166 0,544 24,3 Y 0,548 16,1 Y 53,3 29,38 1,176 0,550 24 Y 0,324 6,4 Y 0,0 19,75 0,324 0,324 6 Y 0,675 9,1 Y 0,0 13,48 0,675 0,675 9,5 Y 0,740 11,3 Y 0,0 15,27 0,730 0,730 13,3 Y 0,800 15,8 Y 0,0 19,75 0,800 0,800 17,6 Y 0,535 6,2 Y 0,0 11,59 0,535 0,535 10,3 Y 2,214 19,5 Y 0,0 8,81 2,214 2,214 29,9 Y 0,919 17,6 Y 0,0 19,14 0,919 0,919 22,3 Y 0,422 10,4 Y 0,0 24,67 0,422 0,422 12,3 Y 0,888 16,2 Y 0,0 18,24 0,888 0,888 19 Y 0,799 24,2 Y 0,0 30,28 0,829 0,829 26,4 Y 0,358 10 Y 0,0 27,96 0,353 0,353 8,4 Y 0,710 20,3 Y 0,0 28,59 0,630 0,630 21,6 Y 0,961 12,3 Y 0,0 12,80 0,957 0,957 26,6 Y 1,064 8,6 Y 0,0 8,08 1,064 1,064 12,2 Y 1,126 14,9 Y 0,0 13,23 1,177 1,177 19,6 Y 1,330 Y 0,0 7,60 1,330 1,330 Y 1,390 18,8 Y 0,0 13,53 1,390 1,390 20,5 Y 0,250 4,2 Y 50,0 16,80 0,500 0,250 6,1 Y 0,958 8,8 Y 0,0 9,19 0,958 0,958 9,8 Y 1,250 25,4 Y 0,0 20,32 1,250 1,250 32,5 Y 0,980 Y 0,0 12,40 0,980 0,980 Y 1,054 9,9587 Y 0,0 9,45 1,022 1,022 12,7151 Y 1,050 Y 0,0 13,90 1,050 1,050 Y 0,980 26 Y 0,0 26,53 0,980 0,980 32,7 Y 0,850 Y 0,0 9,33 0,710 0,710 Y 0,588 17,68 N 0,0 30,05 0,583 0,583 21,45 N

LNEC - Proc. 0204/121/20079

PA % PA Mass loss uncoated (mg/dm2) area 0,0 4,25 2,6 25,92 0,0 21,31 0,0 1,69 0,0 33,22 3,0 40,21 0,0 18,71 0,0 22,15 5,0 18,85 6,4 21,55 4,9 20,04 6,3 27,84 2,6 20,82 2,9 21,75 53,3 44,67 53,2 43,64 0,0 18,52 0,0 14,07 0,0 18,22 0,0 21,99 0,0 19,25 0,0 13,50 0,0 24,25 0,0 29,18 0,0 21,40 0,0 31,85 0,0 23,81 0,0 34,29 0,0 27,79 0,0 11,47 0,0 16,65 0,0 8,80 0,0 14,75 50,0 24,40 0,0 10,23 0,0 26,00 0,0 15,90 0,0 12,44 0,0 14,80 0,0 33,37 0,0 10,89 0,0 36,81

PA-CPA

0,77 7,76 2,26 -0,58 5,80 9,28 3,45 2,30 5,28 7,41 5,90 8,71 5,01 5,32 24,93 14,26 -1,23 0,59 2,95 2,25 7,66 4,70 5,11 4,51 3,15 1,57 -4,15 5,69 14,98 3,38 3,42 1,20 1,22 7,60 1,04 5,68 3,50 2,99 0,90 6,84 1,56 6,75

Section

Sealing process

Thickness Class

Alloy

S S H S S H S H S S S S S S H H H H S S S S H S S H S H S S S U S H S S U S U U U H

C HW HW HW HW HW HW HW HW HW HW HW HW HW HW HW HW C HW C C C HW HW C C HW HW HW C HW C C HW C HW HW C HW C C C

15 10 10 10 10 15 10 10 15 15 15 15 5 5 15 15 10 10 15 10 10 10 10 10 10 10 10 10 5 10 15 15 15 10 15 10 15 10 10 10 15 20

AA 6063 Unknow AA 6060 AA 6060 AA 6060 Unknow AA 6060 AA 6060 AA 6063 AA 6060 AA 6063 AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 Unknow AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6060 AA 6063 AA 6060 AA 6060 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060

Colour

Thickness

51


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

1700 1700 1700 1700 1612 1044 1412 1412 1626 1027 1036 1413 1413 1032 1406 1406 1038 1049 1039 1414 1414 1619 1025 1415 1415 1608 1620 1048 1405 1405 1805 400 400 400 401 401 1505 1802 1204 1614 1604 1617

52

Date

04-10-2013 04-10-2013 04-10-2013 04-10-2013 07-10-2013 08-10-2013 08-10-2013 08-10-2013 08-10-2013 09-10-2013 09-10-2013 09-10-2013 09-10-2013 10-10-2013 10-10-2013 10-10-2013 15-10-2013 17-10-2013 22-10-2013 22-10-2013 22-10-2013 22-10-2013 23-10-2013 23-10-2013 23-10-2013 23-10-2013 23-10-2013 24-10-2013 24-10-2013 24-10-2013 24-10-2013 29-10-2013 29-10-2013 29-10-2013 30-10-2013 30-10-2013 30-10-2013 30-10-2013 03-11-2013 05-11-2013 06-11-2013 06-11-2013

CPA Total area 1,295 1,331 1,525 1,512 0,697 0,990 0,687 0,692 0,611 0,970 1,150 0,706 0,760 0,990 0,693 0,687 1,010 1,010 1,390 0,714 0,654 0,836 1,400 0,790 0,806 1,201 0,640 1,010 0,761 0,765 0,660 0,541 0,541 1,958 1,865 1,865 1,222 0,800 1,020 1,745 0,861 0,680

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 1,272 21,4 Y 1,8 16,82 1,301 1,278 26,4 Y 1,308 22,6 Y 1,7 17,28 1,283 1,260 26,2 Y 1,498 26,6 Y 1,8 17,76 1,511 1,484 32,9 Y 1,484 27,2 Y 1,9 18,33 1,511 1,484 32,9 Y 0,697 17,3 Y 0,0 24,81 0,697 0,697 23,9 Y 0,990 16,1 Y 0,0 16,26 0,990 0,990 19,3 Y 0,672 5,7 Y 2,2 8,48 0,698 0,683 9,8 Y 0,677 6,5 Y 2,2 9,60 0,695 0,680 9,7 Y 0,611 10,4 Y 0,0 17,01 0,579 0,579 10,8 Y 0,970 5,7 Y 0,0 5,88 0,970 0,970 5,7 Y 1,150 11 Y 0,0 9,57 1,150 1,150 13,4 Y 0,662 8,3 Y 6,2 12,54 0,728 0,684 12,8 Y 0,716 10,3 Y 5,8 14,39 0,701 0,657 12,8 Y 0,990 21,1 Y 0,0 21,31 0,990 0,990 23,6 Y 0,672 9,4 Y 3,0 13,99 0,689 0,668 15,1 Y 0,666 10,9 Y 3,1 16,37 0,696 0,675 17,6 Y 1,010 11 Y 0,0 10,89 1,010 1,010 10,8 Y 1,010 22,2 Y 0,0 21,98 1,010 1,010 25,1 Y 1,390 10,7 Y 0,0 7,70 1,390 1,390 13,4 Y 0,695 6,2 Y 2,7 8,92 0,750 0,731 10,4 Y 0,635 6,3 Y 2,9 9,92 0,643 0,624 10,3 Y 0,836 6,3 Y 0,0 7,54 0,840 0,840 9,5 Y 1,400 19,4 Y 0,0 13,86 1,400 1,400 21,5 Y 0,767 8,7 Y 2,9 11,34 0,810 0,787 12,5 Y 0,783 9 Y 2,9 11,49 0,809 0,786 14,3 Y 0,862 14,3 Y 28,2 16,58 1,330 0,955 27 Y 0,640 7,2 Y 0,0 11,26 0,912 0,912 24,7 Y 1,010 16 Y 0,0 15,84 1,010 1,010 15,3 Y 0,717 14,9 Y 5,8 20,78 0,804 0,760 21,6 Y 0,721 15,8 Y 5,8 21,91 0,790 0,746 20,7 Y 0,655 6,8 Y 0,8 10,38 0,655 0,650 10,6 Y 0,535 4,3 Y 1,0 8,03 0,541 0,535 6,1 Y 0,535 4,4 Y 1,0 8,22 0,535 0,530 6 Y 1,217 12,5 Y 37,8 10,27 2,014 1,253 19,2 Y 1,116 14,2 Y 40,2 12,72 1,865 1,116 27,8 Y 1,116 16,8 Y 40,2 15,05 1,865 1,116 24,4 Y 1,222 6,06 Y 0,0 4,96 1,230 1,230 6,5 Y 0,800 8,8 Y 0,0 11,00 0,800 0,800 12 Y 1,000 14,3 Y 2,0 14,30 1,020 1,000 20,3 Y 1,745 122,9 Y 0,0 70,43 1,505 1,505 100,5 Y 0,861 16,3 Y 0,0 18,93 0,861 0,861 19,6 Y 0,680 10,4 Y 0,0 15,29 0,680 0,680 14,3 Y

PA % PA Mass loss uncoated (mg/dm2) area 1,8 20,66 1,8 20,79 1,8 22,17 1,8 22,17 0,0 34,28 0,0 19,49 2,1 14,35 2,2 14,26 0,0 18,65 0,0 5,88 0,0 11,65 6,0 18,71 6,3 19,48 0,0 23,84 3,0 22,60 3,0 26,07 0,0 10,69 0,0 24,85 0,0 9,64 2,5 14,23 3,0 16,51 0,0 11,31 0,0 15,36 2,8 15,88 2,8 18,19 28,2 28,28 0,0 27,10 0,0 15,15 5,5 28,42 5,6 27,75 0,8 16,31 1,0 11,40 1,0 11,32 37,8 15,32 40,2 24,91 40,2 21,86 0,0 5,28 0,0 15,00 2,0 20,30 0,0 66,78 0,0 22,76 0,0 21,03

PA-CPA

3,83 3,52 4,41 3,84 9,47 3,23 5,87 4,66 1,64 0,00 2,09 6,18 5,10 2,53 8,62 9,71 -0,20 2,87 1,94 5,31 6,59 3,77 1,50 4,54 6,70 11,70 15,84 -0,69 7,64 5,83 5,93 3,36 3,10 5,05 12,19 6,81 0,33 4,00 6,00 -3,65 3,83 5,74

Section

Sealing process

Thickness Class

Alloy

S S S S H S S S S S S S S S S S H S S S S S S S S H S S S S S S S H H H S S S S S S

HW HW HW HW HW C HW HW HW HW HW HW HW C HW HW C HW C HW HW HW HW HW HW HW HW C HW HW C MT MT MT HW HW C MT HW HW HW C

15 15 15 15 10 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 10 15 20 20 10 10 15 15 15 15 10 10 15 15 15 15 15 15 10 10 10

AA 6060 AA 6060 AA 6060 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6060 AA 6060 AA 5005 AA 6060 AA 6060 AA 6060 AA 6060 AA 6060 AA 6060 Unknow Unknow AA 6063 AA 6063 AA 6063

Colour

Thickness

LNEC - Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

Date

CPA Total area

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) area area area 2,633 53,1 Y 0,0 20,17 2,633 2,633 47,7 1,773 13,42 Y 0,0 7,57 1,379 1,379 14,29 1,620 Y 0,0 8,19 1,620 1,620 1,030 11,8 Y 0,0 11,46 1,030 1,030 12,5 1,010 14,2 Y 0,0 14,06 1,010 1,010 16,7 0,858 16 Y 0,0 18,65 0,728 0,728 24 1,220 Y 0,0 15,19 1,300 1,300 1,010 15,9 Y 0,0 15,74 1,010 1,010 18,2 1,050 7,7 Y 0,0 7,33 1,050 1,050 10 0,127 2,3 Y 0,0 18,10 0,115 0,115 2,5 0,780 Y 0,0 1,67 0,780 0,780 1,040 10,4 Y 0,0 10,00 1,040 1,040 13,5 0,754 9,5 Y 3,3 12,60 0,776 0,750 14,5 0,729 9,5 Y 3,3 13,03 0,688 0,663 12,7 0,899 6,4 Y 0,0 7,12 0,727 0,727 6,9 0,930 Y 0,0 10,30 0,930 0,930 1,020 10,8 Y 0,0 10,59 1,020 1,020 11,8 0,630 12,4 Y 0,0 19,68 0,630 0,630 14 0,238 4 Y 0,0 16,84 0,251 0,251 5,3 1,010 12 Y 0,0 11,88 1,010 1,010 16,7 0,990 11,9 Y 0,0 12,02 0,990 0,990 15,5 0,940 9,1 Y 6,0 9,68 1,000 0,940 12,4 0,690 15,4 Y 0,0 22,32 0,690 0,690 16,4 0,520 Y 0,0 11,40 0,520 0,520 1,250 Y 0,0 13,50 1,250 1,250 0,581 14,1 Y 0,0 24,25 0,586 0,586 18,1 0,850 Y 0,0 12,70 0,800 0,800 1,200 Y 0,0 8,50 1,300 1,300 0,990 19,1 Y 2,0 19,29 1,010 0,990 26,7 0,410 Y 0,0 12,80 0,410 0,410 0,250 Y 50,0 10,00 0,500 0,250

1627 300 720 1012 1018 1625 715 1029 1047 1605 744 1050 1411 1411 1602 721 1046 1607 1609 1004 1014 1202 1617 736 748 1610 740 727 1207 752 753

07-11-2013 13-11-2013 13-11-2013 13-11-2013 13-11-2013 13-11-2013 14-11-2013 14-11-2013 14-11-2013 18-11-2013 19-11-2013 19-11-2013 19-11-2013 19-11-2013 19-11-2013 20-11-2013 20-11-2013 20-11-2013 21-11-2013 26-11-2013 26-11-2013 26-11-2013 03-12-2013 04-12-2013 04-12-2013 05-12-2013 06-12-2013 11-12-2013 11-12-2013 12-12-2013 23-01-2014

2,633 1,773 1,620 1,030 1,010 0,858 1,220 1,010 1,050 0,127 0,780 1,040 0,780 0,754 0,899 0,930 1,020 0,630 0,238 1,010 0,990 1,000 0,690 0,520 1,250 0,581 0,850 1,200 1,010 0,410 0,500

1625 717 1621 718

28-01-2014 29-01-2014 04-02-2014 05-02-2014

1,423 0,420 1,294 0,200

1,061 0,420 1,294 0,200

1618 05-02-2014

0,769

0,769

1636 06-02-2014

1,725

1634 11-02-2014 1615 1043 742 1041

Y Y Y Y

25,4 0,0 0,0 0,0

13,19 23,40 18,85 14,70

1,419 0,420 1,290 0,200

1,058 0,420 1,290 0,200

17,6

Y

0,0

22,89

0,769

0,769

1,123

10,8

Y

34,9

9,62

0,977

0,712

0,712

13

Y

0,0

18,26

12-02-2014 13-02-2014 20-02-2014 26-02-2014

0,521 1,030 0,890 1,050

0,280 1,030 0,700 1,050

11,6 13 11,5

Y Y Y Y

46,3 0,0 21,3 0,0

1632 26-02-2014

1,635

1,156

17,4

Y

29,3

LNEC - Proc. 0204/121/20079

14 24,4

18,1

PA Sol Stirr Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y

PA % PA Mass loss uncoated (mg/dm2) area 0,0 18,11 0,0 10,36 0,0 8,79 0,0 12,14 0,0 16,53 0,0 32,97 0,0 18,20 0,0 18,02 0,0 9,52 0,0 21,78 0,0 3,43 0,0 12,98 3,4 19,33 3,6 19,16 0,0 9,49 0,0 11,70 0,0 11,57 0,0 22,22 0,0 21,13 0,0 16,53 0,0 15,66 6,0 13,19 0,0 23,77 0,0 13,20 0,0 15,20 0,0 30,89 0,0 13,10 0,0 13,00 2,0 26,97 0,0 13,40 50,0 11,50

PA-CPA

Section

Sealing process

Thickness Class

Alloy

-2,05 2,79 0,60 0,68 2,48 14,32 3,01 2,28 2,19 3,68 1,76 2,98 6,73 6,12 2,37 1,40 0,98 2,54 4,30 4,65 3,64 3,51 1,45 1,80 1,70 6,64 0,40 4,50 7,68 0,60 1,50

H S U S S S U S S S U S S S U U S S S S S S H U U S U U S U S

HW HW C C C HW HW C C HW C C HW HW HW C C HW HW S C HW C C HW HW C MT HW C C

10 15 15 15 15 10 20 15 15 10 10 15 15 15 15 10 10 10 10 15 10 10 10 20 15 10 15 20 10 15 10

AA 6063 AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 Unknow AA 6063 AA 6060 AA 6060 AA 6063 AA 6060 AA 6060 Unknow AA 6060 AA 6060

Y Y Y Y

25,4 0,0 0,0 0,0

17,11 25,60 29,24 16,90

3,91 2,20 10,38 2,20

H S S S

C C HW MT

10 15 10 10

AA 6063 AA 6060 AA 6063 AA 6060

18,7

Y

0,0

24,32

1,43

S

C

10

AA 6063

0,636

9,9

Y

34,9

15,57

5,95

H

C

15

AA 6063

0,712

0,712

16

Y

0,0

22,48

4,21

S

C

10

AA 6063

41,50 12,62 18,50 10,95

0,548 1,040 0,890 1,050

0,293 1,040 0,700 1,050

17,6 14,5 12,5

Y Y Y Y

46,5 0,0 21,3 0,0

60,03 13,94 20,90 11,90

18,52 1,32 2,40 0,95

H S S S

HW C C C

10 10 15 15

AA 6063 AA 6063 AA 6060 AA 6063

15,05

1,821

1,127

25,9

Y

38,1

22,98

7,93

S

MT

10

AA 6063

37,7

Colour

Opaque white Black Opaque white Opaque white Opaque white Opaque white

bronze Opaque white

Thickness

15 12,5

15 17 30 15,6

22 14

53


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

54

Date

CPA Total area

1042 27-02-2014

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 1,010 1,010 13,7 Y 0,0 13,56 1,010 1,010 14,8 Y

1635 28-02-2014

0,890

0,535

9,2

Y

39,9

17,20

0,859

0,516

13,3

Y

39,9

25,79

8,59

H

C

10

1612 03-03-2014

2,218

1,171

26,5

Y

47,2

22,63

2,565

1,410

36,4

Y

45,0

25,82

3,19

H

HW

10

1610 04-03-2014

0,676

0,676

13,8

Y

0,0

20,43

0,961

0,961

21,9

Y

0,0

22,78

2,35

S

HW

15

1626 04-03-2014 1025 05-03-2014

0,548

0,548 1,020

10,7 14,7

Y Y

0,0

1,020

0,538 1,020

11,8 17,2

Y Y

0,0

0,0

19,54 14,41

0,538

1,020

0,0

21,94 16,86

2,40 2,45

S S

HW HW

10 15

1630 1633 1506 1044 1412

05-03-2014 06-03-2014 07-03-2014 11-03-2014 11-03-2014

0,667 1,164 1,170 0,990 0,630

0,667 0,600 1,130 0,990 0,616

19,3 16,5 0,0154 14 5,3

Y Y Y Y Y

0,0 48,5 3,4 0,0 2,2

28,94 27,50 0,01 14,14 8,60

0,696 1,086 1,140 0,990 0,586

0,696 0,560 1,100 0,990 0,573

23,3 17,8 0,0148 14,6 6,8

Y Y Y Y Y

0,0 48,5 3,5 0,0 2,2

33,48 31,79 0,01 14,75 11,87

4,54 4,29 0,00 0,61 3,26

S H S S S

HW HW C C HW

10 10 10 10 15

1412 11-03-2014 1027 12-03-2014 1032 12-03-2014

0,613 1,000 1,010

0,599 1,000 1,010

5,6 10,2 4,8

Y Y Y

2,3 0,0 0,0

9,35 10,20 4,75

0,607 1,000 1,010

0,593 1,000 1,010

7,5 14 4,8

Y Y Y

2,3 0,0 0,0

12,65 14,00 4,75

3,30 3,80 0,00

S S S

HW HW C

15 15 20

1414 1414 1503 1036 1405 1405

12-03-2014 12-03-2014 12-03-2014 13-03-2014 13-03-2014 13-03-2014

0,802 0,798 1,023 1,010 0,703 0,719

0,786 0,782 1,023 1,010 0,664 0,680

5,6 5,7 4,3 13,4 15,8 16,3

Y Y Y Y Y Y

2,0 2,0 0,0 5,5 5,4

7,12 7,29 4,20 13,27 23,80 23,97

0,772 0,821 1,039 1,010 0,707 0,685

0,757 0,805 1,039 1,010 0,667 0,645

7,3 7,6 6,9 17,3 18,6 18,2

Y Y Y Y Y Y

1,9 1,9 0,0 0,0 5,7 5,8

9,64 9,44 6,64 17,13 27,89 28,22

2,52 2,15 2,44 3,86 4,09 4,25

S S S S S S

HW HW C HW HW HW

15 15 15 15 15 15

1629 13-03-2014 1046 20-03-2014

1,107 1,010

0,783 1,010

19,9 21,2

Y Y

29,2 0,0

25,41 20,99

1,237 1,010

0,875 1,010

23,6 25,7

Y Y

29,2 0,0

26,96 25,45

1,55 4,46

H S

C C

10 15

1623 24-03-2014 1413 25-03-2014 1413 25-03-2014

1,138 0,577 0,550

0,640 0,555 0,527

7,5 7,8 7,6

Y Y Y

43,8 3,8 4,2

11,72 14,05 14,42

1,138 0,558 0,581

0,640 0,535 0,558

8,6 9,7 10,2

Y Y Y

43,8 4,1 4,0

13,44 18,13 18,28

1,72 4,08 3,86

H S S

C HW HW

10 15 15

1613 1038 1415 1415

25-03-2014 26-03-2014 26-03-2014 26-03-2014

1,149 1,010 0,615 0,612

0,788 1,010 0,604 0,601

17,8 8,2 4,9 4,9

Y Y Y Y

31,4 0,0 1,8 1,8

22,59 8,12 8,11 8,15

1,192 1,010 0,618 0,631

0,820 1,010 0,607 0,620

26,7 12,5 6,6 7,2

Y Y Y Y

31,2 0,0 1,8 1,7

32,56 12,38 10,87 11,61

9,97 4,26 2,76 3,46

H S S S

HW C HW HW

5 15 15 15

1617 719 1406 1406

26-03-2014 27-03-2014 27-03-2014 27-03-2014

1,230 1,780 0,606 0,623

1,230 1,700 0,584 0,601

19,2

Y Y Y Y

0,0 4,5 3,6 3,5

15,61 5,68 12,67 12,81

1,230 1,780 0,606 0,622

1,230 1,700 0,584 0,600

21,7

Y Y Y Y

0,0 4,5 3,6 3,5

17,64 7,36 18,32 17,83

2,03 1,68 5,65 5,02

S S S S

C HW HW HW

10 15 15 15

7,4 7,7

10,7 10,7

PA % PA Mass loss uncoated (mg/dm2) area 0,0 14,65

PA-CPA

Section

Sealing process

Thickness Class

1,09

S

C

15

Alloy

Colour

AA 6063 bronze Opaque AA 6063 white Opaque AA 6060 white Opaque AA 6063 white Opaque AA 6063 white AA 6063 bronze Opaque AA 6063 white AA 6063 bronze AA 6060 Natural AA 6063 Natural AA 6060 Medium AA 6060 bronze AA 6063 bronze AA 6063 Inox Medium AA 6060 bronze AA 6060 AA 6060 AA 6063 bronze AA 6060 Natural AA 6060 Opaque AA 6060 white AA 6063 bronze Opaque AA 6063 white AA 6063 Natural AA 6063 Opaque AA 6063 white AA 6063 bronze AA 6060 AA 6060 Natural Opaque AA 6063 white AA 6060 AA 6060 Natural AA 6060

Thickness

20 13 12 12 19 18 12 14 15 19

18 22 21 20

22 16

15,5 20 13 18

8 20 18 16 18

LNEC - Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

Date

CPA Total area

CPA CPA Mass CPA Sol CPA % CPA Mass loss coated loss (mg) Stirr uncoted (mg/dm2) area area

PA Total PA Total PA Mass area coated loss (mg) area

PA Sol Stirr

PA % PA Mass loss uncoated (mg/dm2) area

PA-CPA

Section

Sealing process

Thickness Class

1604 27-03-2014 728 28-03-2014

1,953 0,850

0,960 0,800

20,9

Y Y

50,8 5,9

21,77 11,40

1,953 0,850

0,960 0,800

29,1

Y Y

50,8 5,9

30,31 12,70

8,54 1,30

H U

HW C

10 20

1627 2703 720 715 701 1045

28-03-2014 28-03-2014 01-04-2014 02-04-2014 03-04-2014 03-04-2014

1,800 1,020 0,350 1,450 1,000 0,980

1,080 0,510 0,320 1,450 1,000 0,980

14 3,2

40,0 50,0 8,6 0,0 0,0 0,0

12,96 6,27 13,73 13,99 9,00 27,04

1,700 1,050 0,350 1,450 1,000 0,980

1,020 0,520 0,320 1,450 1,000 0,980

29,1 3,9

26,5

Y Y Y Y Y Y

28,7

Y Y Y Y Y Y

40,0 50,5 8,6 0,0 0,0 0,0

28,53 7,50 15,79 15,52 9,50 29,29

15,57 1,23 2,06 1,53 0,50 2,24

H S U U U S

HW HW C HW C C

5 15 20 10 20 10

1620 104 1411 1411

07-04-2014 08-04-2014 08-04-2014 08-04-2014

0,738 1,030 0,579 0,594

0,738 1,013 0,560 0,574

20,2 17,9 11,7 12,5

Y Y Y Y

0,0 1,7 3,3 3,4

27,36 17,67 20,89 21,78

0,710 1,030 0,577 0,597

0,710 1,016 0,557 0,577

28,1 22,4 14,4 14,6

Y Y Y Y

0,0 1,4 3,5 3,4

39,56 22,05 25,85 25,30

12,20 4,38 4,96 3,53

S S S S

HW HW HW HW

10 10 15 15

1602 08-04-2014 300 09-04-2014

0,634 1,520

0,634 1,520

4,4 15,3

Y Y

0,0

6,94 10,07

0,634 1,520

0,634 1,520

4,5 20,6

Y Y

0,0 0,0

7,09 13,55

0,16 3,49

S S

HW HW

10 15

1607 741 1049 103 2701 400 400

09-04-2014 10-04-2014 10-04-2014 14-04-2014 14-04-2014 15-04-2014 15-04-2014

1,244 1,230 1,010 1,382 1,470 0,856

16,3

1,244 1,230 1,010 1,392 1,450 0,847 0,856

0,989 1,200 1,010 1,391 0,720 0,837 0,846

28,4 34,3 13,2 17,6 19,8

Y Y Y Y Y N N

20,5 2,4 0,0 0,0 50,3 1,2

1,2

16,47 8,90 24,55 19,33 13,01 18,21 19,60

18,9

24,8 26,7 9,5 15,4 16,4

Y Y Y Y Y N N

20,5 2,4 0,0 0,1 50,3 1,2

0,847

0,989 1,200 1,010 1,381 0,730 0,846 0,837

1,2

19,10 11,50 28,12 24,66 18,33 21,04 23,42

2,63 2,60 3,56 5,32 5,32 2,82 3,81

H U S S H S S

HW C HW HW HW MT MT

10 15 15 15 25 20 20

1609 15-04-2014

0,576

0,576

10,3

Y

0,0

17,88

0,576

0,576

9,9

Y

0,0

17,19

-0,69

S

HW

10

1619 401 401 2702 2704 1039 1048 1503

15-04-2014 16-04-2014 16-04-2014 19-04-2014 21-04-2014 23-04-2014 24-04-2014 25-04-2014

1,061 1,745 1,798 2,110 1,900 1,010 1,000

1,061 1,716 1,769 1,040 0,930 1,010 1,000 1,042

29,2 35,9 39,1 11,7 13,4 10,2 7 12,2

Y N N Y Y Y Y N

0,0 1,7 1,6 50,7 51,1 0,0 0,0

27,53 20,92 22,11 11,25 14,41 10,10 7,00 11,71

0,938 1,956 1,930 2,160 1,880 1,010 1,000

0,938 1,927 1,901 1,070 0,920 1,010 1,000 1,042

27,6 47,8 50,6 14,7 14,1 12,6 7,5 14,8

Y N N Y Y Y Y N

0,0 1,5 1,5 50,5 51,1 0,0 0,0

29,42 24,80 26,62 13,74 15,33 12,48 7,50 14,20

1,88 3,88 4,51 2,49 0,92 2,38 0,50 2,50

S S S H H S S S

HW HW HW C C C C C

10 15 15 15 20 15 15 15

1637 1801 101 102 740 1050

28-04-2014 29-04-2014 06-05-2014 06-05-2014 06-05-2014 07-05-2014

0,910 0,660 1,059 0,882 0,350 1,010

0,910 0,650 1,058 0,880 0,300 1,010

15,3 10,5 13,4 10,7

Y Y Y Y Y Y

0,0 1,5 0,1 0,2 14,3 0,0

16,81 16,15 12,67 12,16 10,10 15,94

0,919 0,660 1,121 0,885 0,350 1,010

0,919 0,650 1,120 0,884 0,300 1,010

24,4 13,4 19,8 12,2

Y Y Y Y Y Y

0,0 1,5 0,1 0,1 14,3 0,0

26,55 20,62 17,68 13,80 13,90 14,75

9,74 4,46 5,01 1,64 3,80 -1,19

S S S S U S

HW C HW HW C C

5 15 15 15 15 15

LNEC - Proc. 0204/121/20079

16,1

14,9

Alloy

Colour

Opaque AA 6063 white AA 6060 Opaque AA 6063 white AA 6063 AA 6060 AA 6060 AA 6060 AA 6063 Inox Opaque AA 6063 white AA 6060 Natural AA 6060 Natural AA 6060 Opaque AA 6063 white AA 6060 Natural Opaque AA 6060 white AA 6060 AA 6063 bronze AA 6060 Natural AA 6063 AA 6060 AA 6060 Opaque AA 6063 white Opaque AA 6063 white AA 6060 AA 6060 AA 6063 AA 6063 AA 6063 Inox AA 6063 Natural AA 6060 Natural Opaque AA 6060 white AA 5005 AA 6060 AA 6060 AA 6060 AA 6063 Inox

Thickness

13

8,5

16 14 11 31

13 16 14 22 16

11 12

18 23 16 7

20

55


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

Date

736 09-05-2014

56

CPA Total area

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) area area area 0,120 0,120 Y 0,0 10,50 0,120 0,120

PA Sol Stirr Y

PA % PA Mass loss uncoated (mg/dm2) area 0,0 12,50

PA-CPA

Section

Sealing process

Thickness Class

Alloy

2,00

U

C

10

AA 6060

1608 12-05-2014

0,960

0,960

3,1

Y

0,0

3,23

0,960

0,960

5,1

Y

0,0

5,31

2,08

S

HW

10

1614 14-05-2014

0,822

0,822

10,2

Y

0,0

12,42

0,822

0,822

11,2

Y

0,0

13,63

1,22

S

C

10

1617 1047 1012 1018 1029 737

14-05-2014 20-05-2014 21-05-2014 21-05-2014 22-05-2014 27-05-2014

1,140 1,020 1,000 0,990 1,010 1,180

1,140 1,020 1,000 0,990 1,010 1,100

17,2 8,7 10 14 11,9

Y Y Y Y Y Y

0,0 0,0 0,0 0,0 0,0 6,8

15,09 8,53 10,00 14,14 11,78 17,10

1,140 1,020 1,000 0,990 1,010 1,180

1,140 1,020 1,000 0,990 1,010 1,100

20,4 11,7 11,7 16,6 15,8

Y Y Y Y Y Y

0,0 0,0 0,0 0,0 0,0 6,8

17,89 11,47 11,70 16,77 15,64 18,20

2,81 2,94 1,70 2,63 3,86 1,10

S S S S S U

C C C C C MT

10 15 15 20 15 15

1412 1412 1014 1405 1405 1004 1026 1414 1414 744 1025 717 727 752 1415 1415 1413 1413

27-05-2014 27-05-2014 28-05-2014 28-05-2014 28-05-2014 29-05-2014 29-05-2014 29-05-2014 29-05-2014 04-06-2014 05-06-2014 11-06-2014 11-06-2014 12-06-2014 18-06-2014 18-06-2014 19-06-2014 19-06-2014

0,667 0,700 1,010 1,154 1,127 1,010 1,010 0,709 0,658 1,350 1,010 0,950 1,550 0,560 0,645 0,636 0,782 0,759

0,643 0,676 1,010 1,062 1,035 1,010 1,010 0,687 0,637 1,200 1,010 0,900 1,550 0,560 0,632 0,623 0,764 0,740

6,7 7,6 11,97 19,1 19,4 4,1 4,9 7,8 7,5

3,6 3,4 0,0 8,0 8,2 0,0 0,0 3,1 3,2 11,1 0,0 5,3 0,0 0,0 2,0 2,0 2,3 2,5

10,42 11,24 11,85 17,98 18,74 4,06 4,85 11,35 11,77 6,07 28,51 11,43 13,93 7,14 8,70 8,99 13,87 14,46

0,667 0,667 1,010 1,210 1,120 1,010 1,010 0,738 0,688 1,350 1,010 0,950 1,550 0,560 0,627 0,636 0,776 0,794

0,643 0,643 1,010 1,119 1,028 1,010 1,010 0,716 0,666 1,200 1,010 0,900 1,550 0,560

8,7 9,5 15,2 28,6 26,2 4,6 6,8 13,2 12,1

13,53 14,77 15,05 25,56 25,49 4,55 6,73 18,44 18,17 9,40 33,17 13,65 16,30 7,15

3,11 3,53 3,20 7,57 6,74 0,50 1,88 7,08 6,39 3,33 4,65 2,22 2,37 0,01

0,614

7,3 8,2 14,1 14,6

2,1

11,89

3,19

0,623 0,758 0,775

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y

3,6 3,6 0,0 7,5 8,2 0,0 0,0 3,0 3,2 11,1 0,0 5,3 0,0 0,0

5,5 5,6 10,6 10,7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y

2,0 2,3 2,4

13,16 18,60 18,84

4,17 4,73 4,38

S S S S S S S S S U S U S U S S S S

HW HW C HW HW HW C HW HW MT HW C MT C HW HW HW HW

15 15 15 20 20 15 10 25 25 15 15 20 10 10 10 10 15 15

1605 19-06-2014 1406 20-06-2014 1406 20-06-2014

3,600 0,583 0,589

3,041 0,571 0,577

84,2 8,4 8,5

Y Y Y

15,5 2,1 2,0

27,69 14,71 14,73

3,646 0,591 0,590

3,080 0,580 0,578

89,1 11,7 11,9

Y Y Y

15,5 1,9 2,0

28,92 20,17 20,59

1,24 5,46 5,86

H S S

HW HW HW

10 15 15

1621 1411 1411 1637 1411 1411 1411 1411

0,502 0,700 0,681 1,345 0,897 0,886 0,648 0,640

0,502 0,656 0,638 1,345 0,861 0,850 0,630 0,622

13 22,5 23,3 26,8 13,6 14,6 11,4 12,1

Y Y Y Y Y Y Y Y

0,0 6,3 6,3 0,0 4,0 4,1 2,8 2,8

25,89 34,30 36,52 19,93 15,80 17,18 18,10 19,45

0,501 0,687 0,747 1,345 0,908 0,920 0,653 0,650

0,501 0,644 0,703 1,345 0,872 0,883 0,636 0,633

18,5 26,3 31 33,2 15,9 15,8 13,2 12,8

Y Y Y Y Y Y Y Y

0,0 6,3 5,9 0,0 4,0 4,0 2,6 2,6

36,93 40,84 44,10 24,68 18,23 17,89 20,75 20,22

11,04 6,54 7,58 4,76 2,44 0,72 2,66 0,77

S S S S S S S S

HW HW HW HW HW HW HW HW

15 15 15 5 15 15 15 15

24-06-2014 25-06-2014 25-06-2014 25-06-2014 17-07-2014 17-07-2014 17-07-2014 17-07-2014

28,8

33,5

Colour

Opaque AA 6063 white Opaque AA 6063 white Opaque AA 6063 white AA 6063 bronze AA 6063 bronze AA 6063 bronze AA 6063 bronze AA 6060 Medium AA 6060 bronze AA 6060 AA 6063 Natural AA 6060 Natural AA 6060 AA 6063 bronze AA 6063 Natural AA 6063 Natural AA 6063 AA 6060 AA 6063 bronze AA 6060 AA 6060 AA 6060 AA 6060 Natural AA 6060 AA 6063 Natural AA 6063 Opaque AA 6060 white AA 6063 Natural AA 6063 Opaque AA 6063 white AA 6063 Natural AA 6063 AA 6063 AA 6060 Black AA 6060 Natural AA 6060 AA 6060

Thickness

11,6 13 12 19 23 22 18

20 21 23 22 15 28

19

11,4 18,4

16,4 17,8

22,4 25

24 19

LNEC - Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

Date

CPA Total area

1700 30-07-2014 1700 30-07-2014

CPA CPA Mass CPA Sol CPA % CPA Mass loss PA Total PA Total PA Mass PA Sol coated loss (mg) Stirr uncoted (mg/dm2) area coated loss (mg) Stirr area area area 2,190 1,134 24,7 Y 48,2 21,78 2,217 1,148 28 Y 2,164 1,120 23,1 Y 48,2 20,63 2,190 1,134 27,2 Y

1612 27-08-2014

1,030

0,485

8,9

Y

52,9

18,36

1,030

0,485

12,7

Y

52,9

26,20

7,84

H

HW

10

1626 28-08-2014 1043 10-09-2014

1,472 1,100

0,948 1,100

20,7 21,3

Y Y

35,6 0,0

21,83 19,36

1,472 1,100

0,948 1,100

25,5 23,6

Y Y

35,6 0,0

26,89 21,45

5,06 2,09

H S

HW C

10 15

1639 22-09-2014 741 25-09-2014 1506 26-09-2014

0,970 1,350 1,204

0,404 1,100 1,188

11,1

58,3 18,5 1,3

27,48 11,09 9,09

0,970 1,350 1,109

0,404 1,100 1,093

13,7

10,8

Y Y Y

12,4

Y Y Y

58,3 18,5 1,4

33,91 12,81 11,34

6,44 1,72 2,25

H U S

C C C

10 15 10

1632 29-09-2014

0,530

0,530

12,4

Y

0,0

23,40

0,530

0,530

15,4

Y

0,0

29,06

5,66

S

MT

10

1624 30-09-2014 743 01-10-2014

0,701 0,900

0,701 0,830

6,2

Y Y

0,0 7,8

8,84 10,40

0,695 0,900

0,695 0,830

9,3

Y Y

0,0 7,8

13,38 14,79

4,54 4,39

S U

HW HW

20 10

1615 01-10-2014

1,285

0,657

13,7

Y

48,9

20,86

1,285

0,657

18,8

Y

48,9

28,62

7,76

H

HW

15

1619 719 1046 728 1044 1406 1406 300 1027 1032

01-10-2014 02-10-2014 02-10-2014 03-10-2014 07-10-2014 07-10-2014 07-10-2014 08-10-2014 08-10-2014 08-10-2014

0,859 1,310 1,010 0,850 1,010 0,512 0,518 1,370 1,000 1,000

0,859 1,200 1,010 0,850 1,010 0,489 0,495 1,370 1,000 1,000

20,2

0,0 8,4 0,0 0,0 0,0 4,5 4,4 0,0 0,0 0,0

23,53 21,09 20,40 14,44 12,48 22,49 21,82 9,34 10,30 2,50

0,859 1,310 1,010 0,850 1,010 0,531 0,522 1,370 1,000 1,000

0,859 1,200 1,010 0,850 1,010 0,509 0,500 1,370 1,000 1,000

18,8

12,6 11 10,8 12,8 10,3 2,5

Y Y Y Y Y Y Y Y Y Y

13 14,8 15,1 16 16,2 3,7

Y Y Y Y Y Y Y Y Y Y

0,0 8,4 0,0 0,0 0,0 4,1 4,2 0,0 0,0 0,0

21,90 23,89 21,29 16,45 12,87 29,08 30,20 11,68 16,20 3,70

-1,63 2,80 0,89 2,01 0,40 6,58 8,38 2,34 5,90 1,20

S U S U S S S S S S

HW HW C C C HW HW HW HW C

10 10 15 25 10 15 15 15 15 15

1415 08-10-2014

0,684

0,667

7,2

Y

2,5

10,79

0,739

0,722

10,5

Y

2,3

14,54

3,75

S

HW

15

1415 1036 1414 1414

08-10-2014 09-10-2014 09-10-2014 09-10-2014

0,698 0,990 0,773 0,749

0,681 0,990 0,748 0,724

6,9 6 8,3 8,4

Y Y Y Y

2,4 0,0 3,2 3,3

10,13 6,06 11,10 11,60

0,722 0,990 0,760 0,733

0,705 0,990 0,735 0,708

10,6 13,3 10,6 10,9

Y Y Y Y

2,4 0,0 3,3 3,4

15,04 13,43 14,42 15,40

4,90 7,37 3,33 3,79

S S S S

HW HW HW HW

15 15 15 15

1608 13-10-2014 1049 15-10-2014 1602 15-10-2014

0,932 1,010 0,164

0,684 1,010 0,164

9,1 17,9 0,6

Y Y Y

26,6 0,0 0,0

13,30 17,72 3,65

0,911 1,010 0,164

0,669 1,010 0,164

12 20,9 0,9

Y Y Y

26,6 0,0 0,0

17,94 20,69 5,48

4,64 2,97 1,83

S S S

MT HW MT

10 15 10

1607 16-10-2014

0,998

0,998

15,8

Y

0,0

15,83

0,998

0,998

17,4

Y

0,0

17,43

1,60

S

MT

10

1613 20-10-2014

1,574

1,359

6,1

Y

13,7

4,49

1,605

1,386

16,7

Y

13,7

12,05

7,56

H

HW

10

LNEC - Proc. 0204/121/20079

20,6

21,5

PA % PA Mass loss uncoated (mg/dm2) area 48,2 24,39 48,2 23,99

PA-CPA

Section

Sealing process

Thickness Class

Alloy

2,61 3,36

H H

HW HW

10 10

AA 6060 AA 6060

Colour

Opaque AA 6060 white Opaque AA 6063 white AA 6060 Natural Opaque AA 6060 white AA 6060 Natural AA 6063 Natural Opaque AA 6063 white Opaque AA 6063 white AA 6060 Natural Opaque AA 6063 white Opaque AA 6060 white AA 6060 Natural AA 6063 bronze AA 6060 Natural AA 6063 Natural AA 6063 bronze AA 6063 bronze AA 6060 Natural AA 6063 Inox AA 6063 bronze Medium AA 6060 bronze Medium AA 6060 bronze AA 6063 bronze AA 6063 Yellow AA 6063 Yellow Opaque AA 6063 white AA 6063 Inox AA 6063 Opaque AA 6063 white Opaque AA 6063 white

Thickness

13 12 25 12 12 12 29

15,4 15 19 17 19,6 19,6 17 19 17 21,4 21,4 24 24 24 13 21

13 14

57


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence

1617 736 1025 1412

58

Date

CPA Total area

CPA coated area

CPA Mass CPA Sol CPA % CPA Mass loss loss (mg) Stirr uncoted (mg/dm2) area

20-10-2014 21-10-2014 21-10-2014 21-10-2014

1,416 0,960 1,000 1,061

1,120 0,960 1,000 1,043

21,8

1627 21-10-2014

1,620

1640 21-10-2014 1413 22-10-2014 1503 22-10-2014

PA Total PA Total PA Mass area coated loss (mg) area

20,9 0,0 0,0 1,7

19,46 16,86 8,60 9,40

1,375 0,960 1,000 1,038

1,080 0,960 1,000 1,019

24,3

8,6 9,8

Y Y Y Y

1,620

21,1

Y

0,0

13,02

1,660

0,622 0,978 1,040

0,622 0,966 1,040

17,8 22 18

Y Y Y

0,0 1,2 0,0

28,64 22,77 17,31

1604 22-10-2014 1045 23-10-2014 1405 23-10-2014

1,607 0,980 1,001

1,000 0,980 0,951

18,5 18,7 15,6

N Y Y

37,8 0,0 5,0

1631 740 1039 1048 2706 2706 1411 744 1050 1618 754

23-10-2014 24-10-2014 29-10-2014 30-10-2014 03-11-2014 04-11-2014 05-11-2014 12-11-2014 12-11-2014 12-11-2014 13-11-2014

1,240 1,000 1,010 1,000 1,180 1,840 0,757 1,840 1,010 0,741 1,000

0,743 1,000 1,010 1,000 1,180 0,920 0,746 1,840 1,010 0,741 1,000

18,8

Y Y Y Y Y Y Y Y Y Y Y

1609 1012 727 1029 1047 752 1204 1004 1014 713 1026 2704 2702

13-11-2014 19-11-2014 20-11-2014 20-11-2014 20-11-2014 21-11-2014 25-11-2014 26-11-2014 26-11-2014 27-11-2014 27-11-2014 27-11-2014 01-12-2014

0,430 1,000 1,200 1,010 1,020 0,520 1,200 1,010 1,010 0,800 1,010 2,950 1,810

0,430 1,000 1,200 1,010 1,020 0,520 1,000 1,010 1,010 0,800 1,010 1,470 0,903

7,9 16,7

1640 1202 753 1207 721

02-12-2014 04-12-2014 05-12-2014 10-12-2014 11-12-2014

1,032 1,040 0,890 0,990 1,000

1,032 1,000 0,890 0,930 1,000

9,1 10,9 11,4 8,8 17,2 12,7 14,5

14,9 16,7 23,7 2,7 14,5 24,6 17,5 9,6 46 7,7 20,6

PA Sol Stirr

PA % PA Mass loss uncoated (mg/dm2) area

PA-CPA

Section

Sealing process

Thickness Class

Alloy

9,3 13,3

Y Y Y Y

21,5 0,0 0,0 1,8

22,50 24,46 9,30 13,05

3,04 7,60 0,70 3,66

S U S S

C C HW HW

10 15 15 15

AA 6063 AA 6060 AA 6063 AA 6060

1,660

26,6

Y

0,0

16,02

3,00

S

HW

10

AA 6063

0,596 0,953 0,980

0,596 0,941 0,980

20,6 26,6 19

Y Y Y

0,0 1,3 0,0

34,55 28,27 19,39

5,92 5,49 2,08

H S S

C HW C

10 10 15

AA 6060 AA 6063 AA 6060

18,51 19,08 16,40

1,561 0,980 1,030

0,996 0,980 0,980

22,6 21,4 19,4

N Y Y

36,2 0,0 4,9

22,69 21,84 19,80

4,18 2,76 3,39

H S S

HW C HW

10 15 15

AA 6063 AA 6063 AA 6060

40,1 0,0 0,0 0,0 0,0 50,0 1,5 0,0 0,0 0,0 0,0

25,30 8,60 9,01 10,90 9,66 9,57 23,06 5,09 12,57 19,57 15,00

1,240 1,000 1,010 1,000 0,936 1,780 0,761 1,840 1,010 0,749 1,000

0,743 1,000 1,010 1,000 0,936 0,890 0,750 1,840 1,010 0,749 1,000

19,9

Y Y Y Y Y Y Y Y Y Y Y

40,1 0,0 0,0 0,0 0,0 50,0 1,4 0,0 0,0 0,0 0,0

26,78 12,00 9,70 12,30 14,63 18,54 37,20 6,98 14,55 24,71 20,60

1,48 3,40 0,69 1,40 4,97 8,97 14,14 1,89 1,98 5,14 5,60

H U S S U U S U S S U

HW C C C HW HW HW C C C C

5 15 10 15 15 15 15 20 15 10 20

AA 6063 AA 6060 AA 6063 AA 6063 AA 6063 AA 6063 AA 6063 AA 6060 AA 6063 AA 6063 AA 6060

Y Y Y Y Y Y Y Y Y Y Y Y Y

0,0 0,0 0,0 0,0 0,0 0,0 16,7 0,0 0,0 0,0 0,0 50,2 50,1

18,37 16,70 11,15 14,75 16,37 8,93 23,70 2,67 14,36 11,90 24,36 11,90 10,63

0,400 1,000 1,200 1,010 1,020 0,520 1,200 1,010 1,010 0,800 1,010 2,920 1,860

0,400 1,000 1,200 1,010 1,020 0,520 1,000 1,010 1,010 0,800 1,010 1,451 0,927

8 19

Y Y Y Y Y Y Y Y Y Y Y Y Y

0,0 0,0 0,0 0,0 0,0 0,0 16,7 0,0 0,0 0,0 0,0 50,3 50,2

20,00 19,00 19,78 17,13 20,20 14,85 30,80 3,17 15,15 13,10 29,01 14,82 13,17

1,63 2,30 8,63 2,38 3,82 5,92 7,10 0,50 0,79 1,20 4,65 2,92 2,54

S S U S S U H S S U S H H

HW C MT C C C HW HW C C C C C

10 15 15 15 15 15 15 15 15 10 15 20 15

Y Y Y Y Y

0,0 3,8 0,0 6,1 0,0

44,56 7,70 16,90 22,15 6,10

1,082 1,040 0,890 0,990 1,000

1,082 1,000 0,890 0,930 1,000

Y Y Y Y Y

0,0 3,8 0,0 6,1 0,0

45,28 10,70 19,80 31,51 8,90

0,72 3,00 2,90 9,35 2,80

S S U S U

C HW C HW C

10 15 20 10 10

9,8 12,3 13,7 16,5 27,9 14,7 18,5

17,3 20,6 30,8 3,2 15,3 29,3 21,5 12,2 49 10,7 29,3

Colour

Opaque white Black bronze Black Medium bronze Opaque white Natural Natural Opaque white Natural bronze Opaque white Natural Natural Natural

Black bronze Inox bronze Black Opaque AA 6063 white AA 6063 bronze AA 6060 Natural AA 6063 bronze AA 6063 Natural AA 6060 Natural Unknow Natural AA 6063 bronze AA 6063 Natural AA 6060 Natural AA 6063 bronze AA 6063 AA 6063 Opaque AA 6063 white Unknow Natural AA 6060 Natural Unknow Natural AA 6060

Thickness

16 18 22,5 13,8 16 13,3 19 12 19,3 6 16 21

17 19 14

15 21 20 19 19 20 17 21

14 21 12

LNEC - Proc. 0204/121/20079


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

ANNEX III List of Inspected Anodizing Plants

LNEC - Proc. 0204/121/20079

59


STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence 101 102 103 104 106 300 400 401 701 705 713 715 717 718 719 720 721 727 728 729 736 737 738 740 741 742 743 744 745 746 748 749 752 753 754 755 1004 1012 1014 1018 1025 1026 1027 1029 1032 1036 1038 1039 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1202 1204 1207 1213

Country Austria Austria Austria Austria Austria Cyprus Slovakia Slovakia Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Italy Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Spain Switzerland Switzerland Switzerland Switzerland

LNEC - Proc. 0204/121/20079

Company Name Christof Piesslinger Agru. Oberflächentechnik GmbH Stiefler Gesellschaft m.b.H. Collini Ges Eloxierwerk GesmbH Muskita Aluminium Industries Ltd. Sapa Profily a.s. Cortizo Slovakia a.s. Oxicolor S.R.L. Ossidan Metra Colors Pandolfo Alluminio Srl Oxidal Bagno Sapa Profili Ossida S.r.l. Anodall S.p.A. Tecnoal ANOFOR NECE SPA AG. System srl FAPIM MERAL GALLOX GEAL PONZIO s.r.l. ALUCOLOR OX ANOXIDALL ISA ITALFINISH HYDRO BUILDING SYSTEM s.p.a. SITAL ANODICA LUALMA ANODICA srl NUOVA COROXAL S.R.L. ALOXALL s.r.l. UNITED ANODIZERS SRL DECORAL S.A. ANODIAL ESPAÑOLA, S.L. HYDRO ALUMINIUM EXTRUSION SPAIN, S.A. HYDRO BUILDING SYSTEMS, S.L. SOPENA METALES S.L. ANODICOLOR Productos Balumco, S.A. ANODIZADOS CORTIZO S.A. INGALZA S.A. Extrusionados de Galicia S.A. (EXTRUGASA) EXL QUINTAGLASS, S.L. Lacado y Anodizado del Aluminio S.A. (LANOAL) Extrusionados del Aluminio S.A. (EXTRUAL) Aluminios Cándido, S.A. (ALUCANSA) Aluminios Cortizo Canarias, S.L. Anodizados Ayuso, S.L.U. Galimetal, S.A. Apliband, S.L. Extrusiones de Toledo, S.A. Anodizados Ebro, S.A. Extrusionados y Tratamientos del Color, S.A. EXTRUCOLOR Aluminios Cortizo Manzanares, S.L. Strugal 2 SL Bürox AG BWB Altenrhein AG Alu Menziken Extrusion AG BWB - Buchser AG

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Licence 1405 1406 1409 1411 1412 1413 1414 1415 1503 1505 1506 1600 1602 1604 1605 1607 1608 1609 1610 1612 1613 1614 1615 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1700 1801 1802 1803 1804 1805 1806 2701 2702 2703 2704 2706

62

Country Portugal Portugal Portugal Portugal Portugal Portugal Portugal Portugal Greece Greece Greece Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Turkey Hungary Poland Poland Poland Poland Poland Poland China China China China China

Company Name Extrusal, Companhia Portuguesa de Extrusão, S.A. Metalfer, Metalúrgica de Fermentelos , S.A. Portalex Alumínio, S.A. ALFA SUL, Alumínios do Sul, Lda. ANICOLOR, Alumínios, Lda NAVARRA Extrusão de Alumínio, S.A. LACBRAGA, Lda LACOVIANA Exalco S.A. ALUMIL S.A. ANALKO Ltd. Fenis Alüminyum San ve Tic A.S. Cuhadaroglu Metal San. Ve. Tic. A.S. Astas Alüminyum Sanayi ve Tic. A.S. Asas Alüminyum San ve Tic. A.S. Saray Döküm ve Madeni Aksam San. A.S. Erdoganlar Alüminyum A.S. Alpsan Aluminyum ve Plastik Profil San. A.S. Aykim Metal Sanayi Ve tic. A.S. Arslan Alüminyum Senayi Ve Ticaret Ltd. Sti. Kurtoglu Alüminyum Bakir Kursun Sanayi Ve Ticaret A.S. Burak Alüminyum San.ve Tic. Anonim Şirketi. Alsan Alüminyum Sanayi Ve Ticaret A.S. Nur Alüminyum Ticaret Pazarlama Ltd. Sti. Demirtas Metal Alüminyum Profil Sanayi ve Ticaret A.S. Gençer Alüminyum Profil Sanayi ve Ticaret A.S. Sistem Alüminyum Sanayi ve Ticaret A.S. Çelikler Alüminyum Plastik Sanayi ve Ticaret A.S. ALMAK Alüminyum ve Makina Sanayi Ltd. Sti. TUNA Alüminyum Metal Kimya Ins. San. ve Dis Tic. Ltd. Sti. HAS Aluminyum Sanayi ve Ticaret A.S. Ulusan Alüminyum Sanayi ve Ticaret A.S. Cansan Alüminyum Profil Ins. San. Ve Tic. A.S. Demsaş Metal San. Ve Tic. A.S. ZAHİT ALÜMİNYUM SANAYİ VE TİCARET A.Ş. Alkor Alüminyum Enerji Sanayi Ticaret LTD. STI. Aluneg Alüminyum Sanayi ve Pazarlama LTD Sti Baransan Profil A.S. Beymetal Mimarlik Mühendìslìk Ìnsaat Taahhüt GIDA SAN. LTD. STI AKPA Alüminyum Plastik Sanayi ve Ticaret Ltd. Sti. Formal Alüminum Sanayi ve Ticaret A.Ş. Burak Alüminyum Sanayi Ve Ticaret A.Ş. Mesan Metal Alüminyum Sanayi Ve Ticaret A.Ş. ASIST ALÜMINYUM PROFIL Sanayi Ve Ticaret A.S. Sebat Alüminyum Sanayi Ve Ticaret A.Ş. Sistem Alüminyum San. ve Tic. A.S. SAPA Profiles Kft. SAPA ALUMINIUM Sp. z o.o. FINAL SA EFFECTOR S.A. GRUPA KETY SA ALU-KOLOR Spólka z o.o. Zaklad Uslugowy "Rosa" Sp. z o.o. Foshan Guang Cheng Aluminium Co. Foshan Sanshui Fenglu Aluminium Co. Jiangyin East-China Aluminium Technology CO. Guangdong JMA Aluminium Profile Factory (GROUP) Co. Liao Ning Zhong Wang Group

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

ANNEX IV Statistical Analysis

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Statistical Analysis In the statistical analysis of data carried out, the following mathematical expressions and statistical concepts were used:

Average value The average value of mass loss differences were determined by its arithmetic mean, m. If n values of a variable are given, each value denoted by xi (where i = 1,2, …, n), the arithmetic mean is the sum of all the values xi divided by the total number, n, of values (eq.1). n

∑x m=

i

i =1

(1)

n

Standard Deviation The Standard Deviation, s, is a measure that is used to quantify the amount of variation or dispersion of a set of data values around the mean (eq.2). n

∑ ( x − m)

2

i

s=

i =1

n −1

(2)

Mode The mode is the most frequent value in a data set. In this report was used to indicate to the most frequent interval of mass loss differences.

t Test: paired two sample for means This statistical test compares two independent sets of data and can be used to compare the results of two test methods carried out on the same sample, i.e, when there are matched pairs of results. It allows determining if the differences between the two sets of data are significant or not. The following steps were used: •

First, the null hypothesis was set-up, which assumes that the differences are not significant. Hence the results of the two tests methods under comparison are similar if:

t exp ≤ t tab

(3)

Where:

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texp = is an experimental parameter calculated by the following formula (eq.4):

t exp =

Dm ⋅ N Sm

(4)

N = is the total number of samples tested by the two methods; Dm = is the arithmetic mean of the differences between the two test methods results obtained for each sample; Sm = is the standard deviation relative to the mean of the differences. ttab = is the value of the Studen’s t-distribution the for the significance level of 5% (two sided) and n-1 degrees of freedom

Second, testing of hypothesis: after calculating the parameter texp, we will compare it with the tabled value, ttab.

If the calculated value is greater than the tabled value, then the null

hypothesis is rejected. If the calculated value is less than the tabled value, then the null hypothesis is accepted and it could be stated that there is no significant difference between the two paired samples, and then the results obtained by the two test methods are similar.

The assumptions made by using this type of statistical test are that normal distributions are assumed and the variance of the two samples is equal. The results of the t-Test carried out to the mass loss differences obtained in the QUALANOD survey (Table 2.8) are presented in Table IV.1. In any case the condition (3) is fulfilled, thus the mass loss differences obtained between the two sealing test methods are significant.

Table IV.1 – t-Test (paired two sample) results applied to the average (PA-CPA) mass loss differences (in mg/dm2) obtained in the QUALANOD survey Global Source data

Average (Dm)

Std. Dev. (Sn)

Number of CPA tests (N)

texp

ttaba

Excluding all negative differences Average Std. Dev. (Dm) (Sn)

Data from 20134,2 ± 3,7 391 22,14 1,966 4,4 ±3,6 2014 Only data from 3,7 ±2,9 192 17,68 1,972 3,8 ±2,8 2014 Only data from 4,6 ±4,4 199 14,75 1,972 5,0 ±4,2 2013 CPA mass loss ≤ 30.0 mg/dm2 4,1 ±3,7 382 21,66 1,966 (2013-2014) CPA mass loss > 30.0 mg/dm2 6,3 ±6,4 9 2,953 2,262 (2013-2014) Note: ttab values presented were obtained with the Microsoft EXCEL 2010 program

66

Number of CPA tests (N)

texp

ttaba

376

23,70

1,966

188

18,61

1.973

188

16,32

1,973

-

-

-

-

-

-

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Grubb’s test (single test) The Grubb’s test (single test) can be used to determine whether the largest or the smallest value of a population is an outlier. Note that this test assumes a normal distribution of the population. The application of Grubb’s test to inspections data was done following the procedure indicated in the ASTM Standard E178-08 [18]. In a sample of n values of x arranged in order of increasing magnitude, if the largest value, xn, is the doubtful one, the test criterion will be as follows:

Gn =

( xn − m )

(5)

s

If x1 rather than xn is the doubtful value, then the criterion would be:

G1 =

(m − x1 )

(6)

s

The values of Grubb’s test criteria (Gn, G1) are compared with a critical value (Gcrit) defined by the size of the sample (n) and a significance level. Dealing with outlying observation requires a significance level of 1%. Thus for n=400, Gcrit = 4,0166 [21]. • If G > Gcrit then the value under test could be an outlier. Grubbs test detects one outlier at a time. For multiple outliers, delete the single outlier detected and repeat the Grubb’s test until no outliers are detected. The results of the Grubb’s tests carried out to the mass loss differences obtained in the QUALANOD survey are presented in Table IV.2. Only the largest values were identified as possible outliers.

Table IV.2 – Grubb’s test (single test) results i

xi

m

S

Gi

391

28,4

4,20

3,74

6,46

Yes

390

26,3

4,13

3,54

6,26

Yes

389

24,9

4,08

3,36

6,20

388

20,1

4,02

3,20

5,03

Yes

1

-4,2

4,19

3,74

2,2

No

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Gcrit

4,0166 (n=400)

Outlier

Yes

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

ANNEX V Additional Data from Portuguese QUALANOD’s Product Inspections Survey (2014-2015)

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Additional Data from Portuguese QUALANOD’s Product Inspections Survey (20142015) From the beginning of 2014, in addition to the data collected for the large QUALANOD survey, it has also been collected data concerning several production parameters: anodization temperature and current density, and sealing time (in min/µm), relative to the test specimens subjected to the CPA and PA mass loss tests. The CPA test continued to be performed during 2015 inspections, now for comparison with the PA test results obtained with the reduced immersion time. Data concerning process conditions is reported in Tables V.1 and V2 along with the results of the mass loss differences (2014-2015) and of the mass loss tests (2015). The results of the mass loss tests of 2014 can be consulted in the Annex II.

Table V.1 – Additional Data from Portuguese QUALANOD Product Inspections carried during 2014 relative to several process conditions and (PA-CPA) mass loss differences

1)

License

Date

1412

11-03-2014

Anodizing Temperature (°C) 18,4

Current density (A/dm2)

Sealing time (min/µm)

1,3

6,7

(PA-CPA) mass loss differences1) (mg/dm2) 3,3 3,3

1414

12-03-2014

17

-

1,6

2,5

2,2

1405

13-03-2014

18,2

-

6,9

4,2

4,1

1406 1413

27-03-2014

18

1,02

3,3

5,0

5,7

25-03-2014

18

1,4

5,0

4,1

3,8

1412

27-05-2014

19,3

1,45

-

3,5

3,1

1405

28-05-2014

19

1,6

-

7,6

6,7

1413

19-06-2014

18,5

-

-

4,4

4,7

1406

20-06-2014

19

0,8

-

5,9

5,5

1415

18-06-2014

-

1,5

-

3,2

4,2

1411

08-04-2014

18

1,6

-

7,6

6,6

1411

25-06-2014

19

1,4

3,8

2,1

1,3

1411

17-07-2014

18

1,5

3,8

2,1

1,1

1414

09-10-2014

18

1,5

-

4,3

2,8

1415

08-10-2014

19,1

1,4

-

4,4

4,3

1406

07-10-2014

19

1,15

-

7,3

7,7

1412

21-10-2014

18,6

1,5

8,9

3,6

1413

22-10-2014

19

1,5

0,0

5,5

1405

23-10-2014

18,3

1,5

7,2

3,4

1411

05-11-2014

18

1,2

6,1

14,2

These values were calculated from the results reported on Annex II.

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

Table V.2 – Data from Portuguese QUALANOD Product Inspections carried during 2015 relative to several process conditions and mass loss results Test specimen

Anodizing Temperature (°C)

Current density (A/dm2)

Sealing time (µm/min)

Mass loss results (mg/dm2)

(PA-CPA) mass loss differences (mg/dm2)

Thickness Class (µm) 15

Profile type Solid

18,5

1,3

4,7

28,51

22,50

6,0

Natural Medium bronze Yellow

25

Solid

18,5

1,5

6,9

13,45

11,52

1,9

20

Solid

18,5

1,4

3,1

10,68

8,16

2,5

15

Solid

17

1,4

4,7

10,43

7,77

2,7

Natural

20

Solid

18,2

1,6

4,3

23,04

19,14

3,9

Natural Greyishblue Medium bronze Bronze

10

Hollow

18

1,4

3,5

19,73

18,17

1,6

20

Solid

18

1,2

3,6

25,53

20,84

4,7

25

Solid

17,5

1,5

4,4

16,15

11,49

4,7

15

Solid

18,4

1,4

5,8

9,53

6,66

2,9

Natural

15

Solid

18,5

1,5

5,6

12,58

10,56

2,0

Natural

20

Solid

18

0,9

4,5

65,24

56,04

9,2

Natural Medium bronze Bronze

20

Solid

19

1,2

4,4

15,62

12,74

2,9

15

Solid

18

1,95

3,9

16,89

13,57

3,3

15

Solid

17

1,6

4,2

15,17

11,49

3,7

Colour Bronze

PA13min

CPA

Bronze

15

Solid

17

3,9

14,07

9,97

4,1

Natural

20

Solid

18,5

1,5

5,4

13,26

9,74

3,5

Natural Dark Bronze Medium Bronze

15

Solid

-

-

-

22,20

13,47

8,7

25

Solid

18

1,5

3,6

27,62

22,61

5,1

20

Solid

18

1,4

4,7

11,73

7,33

Bronze

15

Solid

17

1,25

9,5

12,26

7,71

4,6

Natural

20

Solid

18

1,5

3,8

14,95

12,40

2,5

Natural

15

Solid

18

1,5

4,7

22,29

15,70

6,6

Natural Black

15

Solid

18

1,6

6,6

16,78

14,10

2,7

20

Solid

18

-

-

23,45

18,17

5,3

Natural

20

Solid

18

1,33

3,5

17,52

17,06

0,5

72

4,4

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STUDY OF THE NEW CHROMIUM-FREE TEST METHOD FOR THE ASSESSMENT OF SEALING QUALITY OF ANODIC OXIDATION COATINGS Final Report

ANNEX VI Results of the Complimentary Studies on PA test

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Results of the Complimentary Studies on PA test

Effect of the variation of the nitric acid (predip) solution The results of the variation of the nitric acid solution (predip) temperature are presented in Table VI.1 for the anodic coating types A, B, C and D. Table VI.1 – PA test mass loss results obtained with different predip temperatures Predip solution temperature, Tpredip (°C) 15,5

Pa solution temperature1 Tpa (°C) 37,9

12,2

11,5

13,6

13,8

19,3

37,6

12,5

11,9

12,9

12,9

25,1

37,7

13,5

12,9

13,1

13,7

PA13min Mass loss results (mg/dm2) A

B

C

major mass loss difference with ∆Tpredip

D

1,4 mg/dm2 Anodic coating types:A,B Max. rate: 0,14 mg.dm-2.°C-1

1

Pa – Phosphoric acid

Effect of the phosphoric acid solution temperature The results of the variation of the phosphoric acid (pa) temperature on PA test mass loss results are presented in Table VI.2 for the anodic coating types FC, FM, BC, BM, A and F. The respective CPA test mass loss results are presented in Table VI.3, as well as the mass loss differences between the two test methods, calculated for the standard phosphoric acid solution temperature.

Table VI.2 – PA test mass loss results obtained with different phosphoric acid (pa) temperatures Predip solution temperature, Tpredip (°C)

Pa solution temperature1 Tpa (°C) 35,9

FC

FM

BC

BM

A

F

11,6±0,3

30,7±2,4

13,3±0,6

17,6±1,2

11,4±0,2

11,2±0,1

37,8

13,4±0,0

33,3±1,1

14,1±0,1

18,3±0,3

12,6±0,3

12,9±0,2

39,8 14,1±0,5 36,0±0,3 14,2±0,1 19,6±0,1 13,7±0,3 Rate of mass loss change with ∆Tpa 0,6 1,4 0,2 0,5 0,6 (mg.dm-2.°C-1) 1 Pa – Phosphoric acid ; 2Average mass loss of two replicate test specimens and the respective standard deviation.

14,4±0,2

19,1

PA13min Mass loss results2 (mg/dm2)

0,8

Table VI.3 – CPA test mass loss results and (PA13min-CPA) mass loss differences Predip solution temperature, Tpredip (°C) 19,1

PA13min Mass loss results2 (mg/dm2)

Pa/Cr(IV) solution temperature1 (°C)

FC

FM

BC

BM

A

F

37,7

12,1

30,7

11,5

15,2

10,9

10,3

(mg/dm2)

-0,5

0,0

1,8

2,4

1,4

0,9

(PA13min – CPA) mass loss differences at 38°C (mg/dm2)

1,3

2,6

2,7

3,1

1,7

2,6

(PA13min – CPA) mass loss differences 40°C (mg/dm2)

2,0

5,3

2,7

4,4

2,8

4,1

(PA13min – CPA) mass loss differences at 36°C

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Aluminium alloy dissolution in the PA test solutions Uncoated test specimens of the alloys EN AW-6063 and EN AW-5005 were subjected to the complete PA test procedure. The resultant mass losses are presented in Table VI.4 Table VI.4 – Mass losses of uncoated test specimens of two aluminium alloys in the PA test PA13min Mass loss results (mg/dm2) EN AW-6063 mass loss (mg/dm2) Test area (dm2)

76

EN AW-5005

5,1

4,9

4,7

5,2

9,3

9,2

9,0

9,3

9,4

9,4

0,862

0,845

0,847

0,863

0,706

0,708

0,731

0,728

0,859

0,860

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