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Volume 4 2019

ECONCRETE: BRINGING CONCRETE TO LIFE BIORIGAMI SEAWEED HATCH SUSTAINABLE AND FUNCTIONALIZED INORGANIC BINDER-BIOFIBER COMPOSITES PROGRAMMABLE SOFT ACTUATORS SHOW THE POTENTIAL OF SOFT ROBOTICS

CONTENT About

Innovatieve Materialen (Innovative Materials) is a digital, independent magazine about material innovation in the fields of engineering, construction (buildings, infrastructure and industrial) and industrial design.

A digital subscribtion in 2019 (6 editions) costs € 39,50 (excl. VAT) Members of KIVI and students: € 25,- (excl. VAT)

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Gerard van Nifterik

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Innovative Materials platform: Dr. ir. Fred Veer, prof. Ir. Rob Nijsse (Glass & Transparency Research Group, TU Delft), dr. Bert van Haastrecht (M2I), prof. Wim Poelman, dr. Ton Hurkmans (MaterialDesign), prof.dr.ir. Jos Brouwers, (Department of the Built Environment, Section Building Physics and Services TU Eindhoven), prof.dr.ir. Jilt Sietsma, (4TU.HTM/ Mechanical, Maritime and Materials Engineering (3mE), prof.dr. Pim Groen, (SMART Materials Aerospace Engineering (AE) TU Delft/Holst Centre, TNO), Kris Binon (Flam3D), Guido Verhoeven (Bond voor Materialenkennis/SIM Flanders, Prof. dr. ir. Christian Louter Institut für Baukonstruktion Technische Universität Dresden).

1 News 8 Econcrete: bringing concrete to life

With over half of the world’s population concentrating along coastlines, accelerated coastal development which inflicts severe stress on natural ecosystems is inevitable.

Combined with growing threats of sea level rise and increased storminess, coastlines across the globe require development and retrofitting through protective concrete structures. Concrete is the main construction material globally, accounting for over 70% of coastal and marine infrastructure. Nonetheless, concrete is a poor substrate for biological recrutment, and is considered hostile to marine life mainly due to a combination of material composition and overall design. ECOncrete offers an excellent alternative.

12 BiOrigami

210,000 tons of textile waste is produced in the Netherlands every year - that is equivalent to 350,000,000 pairs of jeans! There are opportunities to use this waste stream as a resource for new materials in a circular economy, however. One such new material is the biocomposite RECURF. This material was developed within the Urban Technology research programme at Amsterdam University of Applied Sciences and consists of a combination of non-rewearable textile fibres and a bio-based plastic. The BiOrigami project sought to explore and develop architectural applications for this new circular biocomposite.

18 Seaweed hatch

This summer MaterialDistrict payed attention to the work of Danish designer Kathryn Larsen. Inspired by medieval techniques, she developed a way to bring it back to modern construction by making sustainable prefabricated seaweed panels for roofs and façades.

22 Sustainable and functionalized inorganic binder-biofiber composites

Annually 16 million m2 of so called wood wool composite boards (WWCB) are produced in Europe. Today, WWCB are made of wood wool strands, water and cement.

WWCB are used in a wide range of applications, like thermal insulation, acoustic insulation, indoor decoration, etc. The material is still popular because their lightweight porous structure which makes them of interest as a filler providing thermal insulation and sound absorbing properties. Nevertheless, there are disadvantages, like the necessarily use of fast setting and hardening of Portland cement (PC). The production of PC is contributing substantially to greenhouse gas emissions resulting in a search for alternative materials and the development of new binder types. In 2012 Guillaume Doudart de la Grée - Eindhoven University of Technology - started his PhD-research to study the performance based design and evaluation of lignocellulosic cement composite boards. Last year he defended his thesis successfully: ‘Development of sustainable and functionalized inorganic binder-biofiber composites’.

26 Programmable soft actuators show the potential of soft robotics

Researchers at TU Delft have developed highly programmable actuators that, similar to the human hand, combine soft and hard materials to perform complex movements. These materials have great potential for soft robots that can safely and effectively interact with humans and other delicate objects.

28 Smart Masterals part 4: Piezoelectrics: the working principle.

32 Enterprise Europe Network (EEN) supports companies with international ambitions. Request for partnership; September 2019

Cover: BIOrigami: Folding line jute laminated onto textile by Floor Beckeringh; page 17

INNOVATIVE MATERIALS 4 2019

NEWS

Aluminium oxynitride armour glass The Air Force Research Laboratory (AFRL) along with the Defense-wide Manufacturing Science and Technology program, developed an aluminium oxynitride based, transparent armour material called ALON. According to AFRL, the transparent ceramic armour provides superior ballistic protection at less than half the weight and thickness over traditional glass laminates.

ALON is a transparent ceramic material composed of aluminium, oxygen and nitrogen. It begins as a powder that is formed into unique shapes and made transparent through the application of high temperature and pressure. The Air Force Research Laboratory and the Defense Production Act Title III program have been working on this material since 2006 Corporation.

Transparent armour is currently used on U.S. Army Blackhawk and Chinook helicopters. ALON’s excellent durability and impact resistance have made it of interest to NASA for scratch pane windows on the International Space Station. The next step is creating a curved window.

AFRL>

A projectile exit point is shown in the ballistic glass (left). The aluminium oxynitride transparent ceramic armour is shown (right) with a bulge and no exit from the projectile. . (foto: AFRL)

How roads cool sizzling cities A study led by Rutgers State University of New Jersey shows how permeable concrete pavement can help to reduce the ‘urban heat island effect’ that causes cities to sizzle in the summer.

This summer, the study titled ’Alleviating urban heat island effect using high-conductivity permeable concrete pavement,’ appeared in the Journal of Cleaner Production.

According to Rutgers, impermeable pavement made of concrete or asphalt covers more than 30 percent of most urban areas and can exceed 60 °C in the summertime. It heats the air, posing human health risks, and surface runoff, threatening aquatic life.

The engineering team at Rutgers developed designs for permeable concrete that is highly effective in handling heat.

Permeable pavement contains large connected pores, allowing

water to drain through and reducing pavement temperature.

Water in pores will also evaporate, reducing pavement surface temperature. Moreover, permeable concrete pavement does a better job reflecting heat than asphalt pavement.

The study found that permeable concrete pavement gives off slightly more heat on sunny days compared with conventional concrete pavement, but 25 to 30 percent less heat on days after rainfall. The engineers improved the design of permeable concrete with high thermal conductivity - meaning it can transfer heat more quickly to the ground - further reducing heat output by 2.5 percent to 5.2 percent.

Incorporating industry byproducts and waste (like fly ash and steel slag) into permeable concrete can increase its economic and environmental benefits.

More at Rutgers>

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NEWS

Mimicking wood’s ultrastructure with 3D printing Researchers at Chalmers University of Technology, Sweden, have succeeded in 3D printing with a wood-based ink in a way that mimics the tipical ‘ultrastructure’ of wood. According to Chalmers, the

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research could revolutionise the manufacturing of green products. Through emulating the natural cellular architecture of wood, they now present the ability to create green products derived from trees, with unique properties -

everything from clothes, packaging, and furniture to healthcare and personal care products.

The way in which wood grows is controlled by its genetic code, which gives it unique properties in terms of porosity, toughness and torsional strength. But wood has limitations when it comes to processing. Unlike metals and plastics, it cannot be melted and easily reshaped, and instead must be sawn, planed or curved. Processes which do involve conversion, to make products such as paper, card and textiles, destroy the underlying ultrastructure, or architecture of the wood cells. But the new technology now presented allows wood to be, in effect, grown into exactly the shape desired for the final product, through the medium of 3D printing.

By previously converting wood pulp into a nanocellulose gel, researchers at Chalmers had already succeeded in creating

NEWS a type of ink that could be 3D printed.

Now, they present a major progression successfully interpreting and digitising wood’s genetic code, so that it can instruct a 3D printer.

It means that now, the arrangement of the cellulose nanofibrils can be precisely controlled during the printing process, to actually replicate the desirable ultrastructure of wood. Being able to manage the orientation and shape means that they can capture those useful properties of natural wood.

According to professor Paul Gatenholm, who has led this research within Chalmers University of Technology’s Wallenberg Wood Science Centre, this

technique allows scientists to move beyond the limits of nature, to create totally new sustainable, green products.

The metals and plastics currently used in 3D printing, could be replaced with a renewable, sustainable alternative.

A further advance on previous research is the addition of hemicellulose, a natural component of plant cells, to the nanocellulose gel. The hemicellulose acts as a glue, giving the cellulose sufficient strength to be useful. Paul Gatenholm’s group has already developed a prototype for an innovative packaging concept. They printed out honeycomb structures, with chambers in between the printed walls, and then managed to encapsulate solid particles inside those

chambers. Cellulose has excellent oxygen barrier properties, meaning this could be a promising method for creating airtight packaging for foodstuffs or pharmaceuticals for example.

Earlier this year, the article ‘Materials from trees assembled by 3D printing – Wood tissue beyond nature limits’ was published in Applied Materials Today More at the Chalmers University of Technology >

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09-05-17 13:19

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NEWS

GEM tower

Photo: Bart van Overbeeke

Almost all festivals in Europe use polluting diesel generators as their power supply. In order to reduce he polluting nature of festivals, associate professor of Innovative Structural Design Faas Moonen started in 2017 with the development of a sustainable alternative, appointing a postdoc and three PDEng researchers to help him. The TU/e researchers and nine companies developed a 21-meter high fold-out tower with solar collectors and a wind turbine. On August 5, the so-called ‘GEM-tower’ was fully erected on the TU/e campus for the first time. (GEM stands for Green Energy Mill).

Most of the energy is generated by a vertical wind turbine weighing 700 kilograms and standing at a height of 18 meters. This height was chosen because wind blows the hardest above 18 meters. If there’s no wind, solar cells ensure stable power generation. As many as 144

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small, flexible thin-foil solar cells adorn the tower. (In addition, the research team is supplying 72 large, flexible solar cells that festival organizers can put on the roofs of their food stalls, lavatory units or tents and connect to the tower’s battery pack.)

The eye-catchers are the 40 coloured solar collectors. These so-called LSC (Luminescent Solar Concentrator) panels were developed at TU/e in the research group of Prof. Michael Debije in the Department of Chemical Engineering and Chemistry. The panels catch incoming rays of light in their plates and transfer them to the edges. In the frames of the panels are solar cells that convert these concentrated light beams into electricity. Because the LSC panels do not need direct sunlight, they are more widely applicable than solar cells. In both the shade and in the sun, they provide energy. Even on a completely cloudy day,

they continue to produce electricity.

The coming year will be devoted to testing this tower. In 2020, this model will be fully operational and will travel along the festivals.

This project, under the name GEM-tower, has been honored as an Interreg Europe project with Eindhoven University of Technology as lead partner. Faas Moonen is the project leader from TU/e and is supported by PDEng researchers Floor van Schie, Patrick Lenaers and Marius Lazauskas and postdoc Ester Pujadas-Gispert. Besides TU/e, nine other partners are involved in the project: IBIS-Power, Double2, Pukkelpop, Off Grid Energy Limited, Dour, RPS, Eurosonic Noorderslag, Flexotels and ZAP. http://www.gem-tower.com/

IngrediĂŤnten voor een betrouwbare en maakbare lijmverbinding

1 oktober 2019

Mikrocentrum, Veldhoven 6e editie van hĂŠt event rond lijmtechnologie

www.mikrocentrum.nl

De trends in lijmen komen aan bod in het lezingenprogramma en op de expo: - Glue 2.0 - Het belang van het gecontroleerd aanbrengen van lijm - Praktijkcases: Verlijming van inserts in high performance carbon parts - Primeur: Onderwaterlijm - Lijmacademie - Versneld laten verouderen van lijmverbindingen om duurzaamheid te beoordelen

MAKE IT MATTER

MAKE IT MATTER MAKE IT MATTER is compiled in collaboration with MaterialDistrict (MaterialDistrict.com). In this section new, and/or interesting developments and innovative materials are highlighted.

Experimental terazzo Experimental Terrazzo was created by collaboration between Spanish tile company Huguet and UK based architectural studio Apt, using common waste materials from construction.

The material is available with visible pieces of brick, wood, or metal.

More at MaterialDistrict>

Tasman Glass A material made from molten waste glass, Tasman Glass is inspired by the landscape in which the designer grew up. The material with its water- and ice mimicking surface is an ode to the rich textures of New Zealand’s Tasman Glacier. The material’s properties, such as structure and light transmittance, allow for diverse applications as surfaces and display in retail, interior and other products.

More at MaterialDistrict>

Sto-Glass Mosaic is one of the oldest art techniques in the world. For thousands of years the small tiles have given facades, floors and other surfaces a timeless appearance. Sto-Glass mosaic gives the designer the possibility to create a unique façade.

Glass mosaic has a number of advantages that other claddings don’t have. The glass mosaic mats are supplied in a size of 30 by 30 cm. This ensures better dimensional stability.

Moreover, the glass mosaic is very easy to clean, is frost resistant and has water absorption of up to half a percent.

More at MaterialDistrict>

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MAKE IT MATTER Mycelium design Mycelium is the network of mushroom ‘roots’. It acts as a natural glue that can bind a biomass together. Krown’s products include packaging material, insulation, wall tiles and much more. Krown 3D prints their reusable moulds with a renewable and recycable biopolymer. These moulds are filled with local agricultural waste, a little water and mycelium that binds it all together. For the structure to grow and gain its strength takes around a week. Once it’s full-grown and dried, it forms a structural, stable and renewable product.

More at MaterialDistrict>

Circular Concrete Cityscapes Circular Concrete Cityscapes by Studio Wae is a concrete tile, inspired on the artwork of M.C. Escher, and used to upgrade any garden, square or street. The geometrical tiles are produced with 75 % recycled materials from Urban Mining. The tiles are 6 cm thick and therefore suitable for light transport.

The tiles have the sustainability label A of NLGreenlabel. The drainage is very good due to the conical shape of the tile. The slight profile on the tiles provides an anti-slip function.

The tiles are applicable both flushed and unflushed.

More at MaterialDistrict>

Recycling glass to better concrete Researchers at Deakin University’s School of Engineering in Australia found that ground recycled or waste glass can be used instead of sand when making polymer concrete, resulting in a stronger, cheaper product. Polymer concrete is a type of concrete that uses resins, to replace lime cement as a binder. This produces a high-strength, water-resistant material suitable for industrial flooring and infrastructure drainage. By substituting ground up recycled glass, the polymer concrete becomes stronger, the researchers found.

Photo: Deakin University More at MaterialDistrict>

Rustiles Handcrafted by industrial designer Ariane Prin in Brittain, Rustiles are made of metal particles and Jesmonite, a composite consisting of a water based acrylic and gypsum. The tiles are available in nine different shades of colours over two different tile sizes. All colours are only originating from different metal particles mix, and various oxidation techniques that Prin has been developing over the years.

More at MaterialDistrict>

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INNOVATIVE MATERIALS 4 2019

ECOncrete

Bringing concrete to life With over half of the world’s population concentrating along coastlines, accelerated coastal development which inflicts severe stress on natural ecosystems is inevitable. Combined with growing threats of sea level rise and increased storminess, coastlines across the globe require development and retrofitting through protective concrete structures. Concrete, or ‘grey infrastructure’ is the main construction material globally, accounting for over 70% of coastal and marine infrastructure. Nonetheless, concrete is a poor substrate for biological recruitment, and is considered hostile to marine life mainly due to a combination of material composition and overall design. Subsequently, concrete based marine infrastructure commonly attract low diversity biological communities; primarily dominated by nuisance and invasive species which are very different to those typical to natural habitats.

As coastal and marine infrastructure continues to expand and replace natural habitats, it is of the utmost importance to ensure that newly constructed and renovated structures are ecologically

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engineered to best suit local species recruitment and the enhancement of ecosystem services. European coastlines are becoming increasingly hardened, especially in response to the growing reali-

zation that rising sea levels and stormier seas will prompt proliferation of coastal defence structures where managed retreat or re-alignment is not an option, as important infrastructure, industrial ac-

INNOVATIVE MATERIALS 4 2019 tivities and residential property require protection. For this reason, the interest in environmentally sensitive technologies is on the rise, creating a new market for solutions such as those developed by ECOncrete Tech LTD. ECOncrete Tech LTD is bringing innovation to the highly traditional field of concrete and coastal construction, through a series of bio-enhancing concrete admixtures and science-based designs. This is done in order to encourage the growth of rich and diverse marine plants and animals onto concrete structures such as seawalls, breakwaters, piers and anchoring systems, while improving structural performance and complying with all standards for marine construction.

debris; making it better suited for the harsh marine environment.

Nature based designs

The concrete composition is only part of the recipe for environmentally sensitive concrete technologies. Nature based designs are a key ingredient for a holistic science-based solution. ECOncrete

develops unique surface textures and 3D designs that mimic features and rugosities that are typical of natural marine substrates, such as oyster shells, coral polyps, furrows and undercuts that provide shelter for diverse communities.

In addition, the designs integrate key habitats and biological niches, such as water retaining features that are seve-

Eco-friendly concrete

Eco-friendly concrete is a possible solution for healthier man-made structures in the marine environment. However, to date, this concept has only been applied towards the construction of artificial reefs for recreational and conservational purposes. Various concrete elements in the shapes of domes or pyramids that are cast from ‘less aggressive’ concrete mixes, allow for better marine growth on the surface of the units. These eco-friendly concrete mixes do not comply with the strict requirements for marine and coastal construction needed for constructing seawalls, pier piles, bridge foundations and the like.

ECOncrete has managed to bridge this technology gap through a win-win solution, of bio-enhancing concrete elements that provide significant ecological uplift in urban waterfronts, ports, marinas and alike. The bio-enhancing concrete admixture replaces approximately 10% of the Portland cement in the concrete with a unique blend of supplementary cementitious materials, most of which are by-products of various industries.

This minute replacement is sufficient for significantly enhancing the biodiversity, species richness, and live cover of marine plants and animals compared to standard ‘grey’ concrete construction elements. Beyond this, the bio-enhancing concrete increases the strength and reduces the vulnerability of the concrete to chloride penetration, as well the forces from waves, boat wakes and floating

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rely lacking from standard engineered solutions.

The designs continue to evolve once introduced into the marine environment and the technology works to enhance the growth of habitat forming species and ecosystem engineers, such as canopy algae, oysters, and corals. These species add layers of complexity to the substrate, similarly to the evolution of a living reef; adding shelter and increasing the attractiveness of the surface for the plants and animals yet to come.

Therefore, by studying the current needs, as well as the historic features of the local ecosystems, coastal and marine infrastructure can be designed, such as living seawalls and breakwaters, with greater biological productivity and ecological value.

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An holistic solution

ECOncrete’s unique combination of science-based bio-enhancing concrete admixtures, complex surface textures, and 3D designs act in synergy to mimic features of natural substrates, inducing the growth of rich and diverse assemblages of plants and animals directly onto the concrete structure. The true beauty being that the life that develops on ECOncrete, not only increases the ecological value of the infrastructure, but also acts to improve their structural performance. Skeletons of calcifying organisms such as oysters, corals, tube worm and coralline algae act as the icing on the cake, encrusting the concrete with a layer of CaCO3 that can reach an average of 2-3 kg per square meter in temperate systems. As mentioned earlier, this layer of bio-protection serves to

reduce the sensitivity of the concrete to chloride attacks, which is often the primary reason that concrete placed in the marine environment degrades. Additionally, the living system that is achieved, acts as a living shield from scour and erosion by sand and water motion across the surface; all adding to the structures lifespan and a reduction in maintenance, as well as making it more adaptive to climate change impacts like increased storminess and sea level rise.

Finally, this calcitic layer also offers a huge carbon offset. Each kilogram of such growth, is offsetting 0.12 kg of CO2.

Now think about an entire waterfront or port, acting as an active carbon sink and top it off with enhanced growth of algae on bio-enhanced concrete elements, further offsetting CO2 through photosynthesis.

INNOVATIVE MATERIALS 4 2019 Industry ready solution

After prolong validation and demonstration of the technology, ECOncrete offers a suite of industry-ready high-performance products, that can be seamlessly integrated into most coastal and marine projects. The technology can be applied for precast as well as on site casting, below and under the water. To facilitate mass production capacity, certain products can be cast using dry-cast machinery.

The company’s current line of products includes Bio-enhancing Armoring Units; Enhanced Seawall and Anchoring Systems; Tide-Pools for beach stabilization, Ecological Pile Encasement (for pile repair/protection), Marine Mattresses for erosion control and protection of UW pipes, and a Bio Active Wall (for non-aqua-

tic applications). In addition, ECOncrete is in the process of developing new products, including interlocking tide pool armor, retaining walls, and ecological solutions for bridge foundations and offshore energy facilities.

Blue is the new green

Environmentally sensitive concrete technologies bring a viable, scalable and sustainable solution that can potentially bridge the ever-growing gap between the need for developing and armouring our coastlines, and the need for sustaining marine resources and coastal ecosystems. To truly make a change on a global scale, the negative consequences of coastal development on marine life must be carefully considered by coastal managers and decision-makers when

developing coastal shoreline protection schemes. Instead of merely asking developers to assess their negative impacts (typically termed EIS - Environmental Impact Statements), regulation should also incentivize minimizing and offsetting negative impacts through implementation of innovative environmentally sensitive technologies. Bio-enhancing concrete elements that protect coastal cities and reduce shoreline erosion, while also enhancing the ecosystem and increasing local biodiversity, can benefit from expedited permitting, reduced environmental penalties, and overall provide a win-win solution.

Shimrit Perkol-Finkel PhD, Co-Founder and CEO

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BiOrigami 210,000 tons of textile waste is produced in the Netherlands every year - that is equivalent to 350,000,000 pairs of jeans. There are opportunities to use this waste stream as a resource for new materials in a circular economy, however. One such new material is the biocomposite RECURF. This material was developed within the Urban Technology research programme at Amsterdam University of Applied Sciences and consists of a combination of non-rewearable textile fibres and a bio-based plastic. The BiOrigami project sought to explore and develop architectural applications for this new circular biocomposite. Combining Japanese origami with digital production technology, BiOrigami explores possible functional, flexible applications of the biocomposite in interior products with high experiential value for use in circular-economy architecture. Origami techniques give the material important characteristics, making it more constructive and flexible with enhanced acoustic qualities.

The use of digital production techniques enables serial production, which could be scaled up at a later stage.

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Various samples

One of the largest waste streams in Amsterdam is textile, which equates to an average of 17 kg of textile waste per resident per year. The majority ends up among the general non-recyclable waste and is incinerated. While the stream of textile waste collected separately continues to grow, over 35% of it is unsuitable for reuse or recycling. This ‘sub-stream’ is reused in low-value applications, such as insulation, but a large proportion of the sub-stream never­ theless remains unused. With a view to identifying value-creation opportunities, the Urban Technology research programme at Amsterdam University of Applied Sciences sought higher-grade uses for these fibres. The biocomposite RECURF was developed by mixing the fibres with bio-based plastic (PLA). Over the past years, the distinctive external features and mechanical properties of textile waste fibres (denim, jute and wool) were examined. Among other things, this has resulted in a sheet material, with unique characteristics, that can be both hard and soft. The BiOrigami project was initiated to identify high-grade, reproducible applications for the biocomposite.

The BiOrigami project examined whether origami techniques and digital production technology could be used to create functionally and aesthetically high-gra-

de applications for the biocomposite RECURF in circular-economy building.

The project involved collaboration with Studio Samira Boon and NEXT Architects.

Different sheets of RECURF

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Various samples by Floor Beckeringh and Dennis van Rijsbergen

Studio Samira Boon is an architecture studio that specialises in creating flexible, dynamic interiors with textile and/or origami structures. Their main focus lies on improving the experiential value of a space with respect to acoustics, climate control and energy efficiency.

NEXT Architects works internationally on urban development, architecture infrastructure and interior design projects. The firm was commissioned by development alliance Amvest/ Hurks to build a circular-economy pavilion in Amsterdam North. In Amsterdam, the Buiksloterham is being developed as a testing ground for the circular-economy city, where experiment, research and innovation are actively encouraged. This local authority initiative is in line with the Government’s objective that as from 2050 all construction must be circular. As Next uses primarily locally recycled materials for construction, BiOrigami and the development of interior applications made of the biocomposite RECURF is therefore perfectly in keeping with this circular objective.

Bico fibre

For the BiOrigami project RECURF was used as a sheet material only. This sheet material is created by hot pressing or rolling

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a soft fibre mat made of 50% textile fibre and 50% bio-based plastic (PLA). The fibre mats may be made with either PLA or PLA Bico fibre. The Bico fibre mat contains PLA fibres with a different melting point, as a result of which the pressed material remains softer and more flexible. The waste textile fibres used were either jute, from old sacks used to ship coffee beans, or denim from old jeans. The pressing transforms the soft fibre mat into a sheet material the thickness, surface roughness, texture and colour of which can vary. This is due to the different variables that can affect properties of the sheet material, namely the type of fibre mat, the melting temperature and the weight of the press. Once pressed, the sheet material is ready for further processing. So far, the technique used most is laser cutting but the material can also be cut with a plotter or punched.

Material driven design

Origami structures are known for their flexibility; they can be very compact when folded yet unfold to a substantial size.

Thanks to the combination of flexible lines and hard surfaces of origami structures, a flat material can acquire important properties such as bearing strength, flexibility and acoustics.

INNOVATIVE MATERIALS 4 2019 The use of digital production techniques enables the creation of complex shapes and forms, which in turn enable new applications. Given its specific appearance and unique characteristics, it was only to be expected that the biocomposite would lend itself to origami techniques. First of all, however, extensive material research was required to explore the various possibilities. Extensive material research based on the Material Driven Design methodology (E. Karena, 2015) was therefore conducted during the first stage of the project. Using different origami structures, the research sought to identify the characteristics of RECURF, which can be either hard or soft or, thanks to the various possible post-treatment techniques, a combination of both stiff and flexible.

The research also examined numerous material options depending on the variables. The chosen waste textile fibre determines the ultimate appearance of the sheet, for example, and the thickness of the sheet varies according to the number of fibre mats stacked. The temperature is another influencing factor, as is the choice of PLA in the fibre mats: standard or bi-component (Bico). PLA melts from 180 C°, the PLA fibres in the Bico mats have a core of ordinary PLA and an external layer of PLA with a melting point of 130 C°. The resulting sheet material is consequently stiff yet softer and more flexible than the standard PLA fibre mat. Another factor is the pressure of the hot press; the higher the pressure, the more dense the sheet material. Texture options, finally, include the choice of a smooth or mat surface and the option of adding textures to the material. Extensive experimentation was carried out with all these variables, in combination with laser cutting or otherwise. At an early stage during the exploration of the material and the different folding techniques, various samples were made to examine which folding patterns were most suitable for the material. As the folding is so crucial, the different methods of creating the folding lines were also examined at length. This resulted in four promising options:

1. A folding line is created by laser cutting a broken dashed line. The folding direction is applied after the laser cutting. This technique is only suitable for single or double layer material.

2. To enable a thicker material to be folded, a laser-cut pattern of RECURF sheet material is laminated onto (recycled) textile.

3. Not locally heating the needle-punched fibre mat creates a soft folding line, eliminating any further operation.

4. A 3D-printed section of flexible PLA is pressed between two laser-cut sheets of RECURF; the flexible PLA forms the folding line.

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INNOVATIVE MATERIALS 4 2019

Detail of a roomdivider by Floor Beckeringh

For each of the above folding methods, a wide range of experiments were carried out using different origami structures and production techniques. Appropriate applications were subsequently sought, the solution directions for which emerged from the research conducted into flexibility, acoustics, translucency and experiential value. Based on these results, several interior application concepts were developed for the circular pavilion.

The most favourable combination of an origami structure, the material RECURF, the digital production technique used and the product function was sought for each concept. The objective in each case was to find a product with a high-quality look and feel, that creates maximum value for the material RECURF and that can be produced in series.

Denim sample by Floor Beckeringh

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Two concepts were chosen for further development. One is a visually attractive wall cladding where the flexible folding lines create a repetitive relief pattern.

The irregular surface of this product enhances the acoustics of the room. The other product is a flexible room divi-

INNOVATIVE MATERIALS 4 2019

Folding line jute laminated onto textile by Floor Beckeringh

der which can be adjusted in different directions thus enabling the level of translucency and the degree of privacy to be regulated.

Both products are currently at a prototype stage but, given the response to their first public presentation at Materi-

alDistrict in March 2019, both have the potential to be further developed into promising products with market potential.

Besides the fact that the use of RECURF in itself offers a solution to the enormous textile waste stream in Amster-

dam, this project also demonstrates that high-quality interior applications for circular-economy building are realisable.

That loops can be closed and materials reused in promising, reproducible products.

Annelies de Leede, with thanks to Floor Beckeringh and Dennis van Rijsbergen BiOrigami is a collaborative project be­ tween Amsterdam University of Applied Sciences, Studio Samira Boon and NEXT Architects Sources consulted Karana E.; Brati B.; Rognoli V.; Zeeuw van der Laan A. (2015) Material Driven Design A method to Design for Material Experiences. https://re.public.polimi.it/retrieve/ handle/11311/979536/98287/MDD%20 article.pdf More info: a.l.m.de.leede@hva.nl

Detail of a wall panel by Dennis van Rijsbergen

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INNOVATIVE MATERIALS 4 2019

Seaweed hatch This summer MaterialDistrict payed attention to the work of Danish designer Kathryn Larsen. Inspired by medieval techniques, she developed a way to bring it back to modern construction by making sustainable prefabricated seaweed panels for roofs and façades.

In the Middle Ages, the island of Læsø, in the north east of Denmark, became famous for its salt industry, and hundreds of salt kilns were built. Wood was used to burn those ovens and as a result the island was soon completely deforested, which left the inhabitants without construction materials for their homes.

Therefore, they started to build their homes from driftwood and thatched the roofs with some kind of seaweed, called eelgrass. In fact, eelgrass is not a grass nor seaweed, but belongs to the a Zostera family, small genus of widely distributed seagrasses, commonly called marine eelgrass or simply eelgrass.

On Læsø ,the application of seaweed on roofs was practiced since the Middle Ages. The process involved a lot of

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INNOVATIVE MATERIALS 4 2019 people and material and happened to be quite a project. At the beginning of the 20th century the majority of roofs on Læsø were covered with seaweed.

This isn’t the case today, however. There are in fact only 19 of these so-called ‘tanghusene’ left, 11 of which are listed buildings.

In the 1930s disease attacked the eelgrass, and it therefore became difficult to maintain the roofs. Making new seaweed roofs was out of the question as many loads (sometimes several hundreds) of seaweed were consumed when constructing just a single roof.

As a building material eelgrass has many ‘modern’ advantages. It’s carbon neutral, naturally fireproof, rot-resistant, carbon negative, and becomes fully waterproof after about a year. Its insulation properties are comparable to mineral wool.

Additionally, the material invites plant growth, giving the effect of a green roof or façade.

As a result, Larsen choses not only to focus on the historical context of the seagrass, but current and future applications of it. Because the seaweed, and the timber, were impregnated with seawater, the materials are much less susceptible to decay. Compared to a normal that-

Construction of a traditional eelgrass roof at Læsø. Pine branches were placed on the remaining rafters and seewead was piled on top. A girl would dance on top of the roof to help the natural binders begin to seal the roof. The final construction would be a meter thick and completely solidify after a week

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INNOVATIVE MATERIALS 4 2019

ched roof, which has a lifespan of about 30-40 years, an eelgrass roof can last for as much as 200 to 400 years.

The Læsø homes served as inspiration for Larsen’s Seaweed architecture project. Since using eelgrass in construction has so many environmental benefits, she aimed to bring the material back to modern architecture by designing prefabricated panels. Larsen used existing research by Studio Seagrass and Tobias Gumstrup Lund Øhrstrøm’s master thesis, in which seaweed was mixed with (natural) binders to create panels.

Larsen aimed to retain the original qua-

lities of eelgrass, so she only used minimal amounts of binders. Using 8 natural non-toxic binders, plant or animal based, as well as water, she created several test panels. The natural binders helped improve the seaweed’s waterproofness, but also made the material more stiff and sometimes brittle.

Currently, Larsen is testing large scale panels of water-applied seaweed on the roof of Copenhagen School of Business (KEA). After about eight months outside, the panels are almost entirely intact, and moss is beginning to grow on the eelgrass.

The installation was sponsored by KEA Campus Service, and all material testing was done with the guidance of KEA’s Material Design Lab. In 2019, Larsen received funding from Boligfondens Spirekasse, to build new prototypes and continue her research. She hopes to test the panels’ u-values, to see what insulation properties they can bring to a construction.

Photos: Kathryn Larsen/Anders Lorentzen/www.visitlaesoe.dk More at Kathryn Larsen: https://kathrynlarsen.com/seaweed-thatch-reimagined

With just 19 seaweed houses left, it requires a great effort to maintain them for posterity. In 2007 the seaweed roofs on Læsø were declared as one of North Jutland’s seven wonders. Nevertheless, the Centre for Building Preservation in Raadvad, Denmark, has estimated that it will cost over €12 million to provide all houses with a new seaweed roof, because the work will also involve an extensive restoration of many of the cottages. Thanks to local passion, foundations, the local museum and municipality, and the Danish state, the community of Læsø was able to secure the island’s seaweed homes of particular conservation interest.

Since 2016 the roofs of three houses will be dressed in new by the local the local thatcher, Henning Johansen.

Video

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RESEARCH

Hierarchical behaviour and failure mechanisms in automotive steel grades

An example of damage mechanisms at different length scales which lead to global failure: (a) a high strain rate (687s-1) tensile deformation of a bainitic steel loaded along the Rolling Direction (RD), (b) contiguous collection of ~1000 SEM micrographs of the fracture sample in (a), (c) the corresponding image processed version of (b) with clear distribution of voids and (d) etched microstructure of the fractured bainitic multiphase steel

Sheet Metal Forming is an important requirement for metal sheet to be employed in automotive applications.

Many experiments and simulations are performed in order to predict the forming limits of steel sheets, which are determined either by observation of the sheets’ failure or deformation localization during various forming processes. In order to enhance the formability at the macroscopic level, a deep understanding of micro-mechanisms of failure is necessary as well as the hierarchical connection through various length scales.

In the current research work, dr.ir. Behnam Shakerifard, under supervision of dr.ir. Jesus Galan Lopez and prof. dr. Leo Kestens, investigates damage initiation micro-mechanisms under static and dynamic loading by advanced experimental characterization techniques and crystal

plasticity based modelling. This research is conducted on the 3rd generation of advanced high strength steels, which are promising candidates for the production of various components of the car Body-In-White.

The topology of 2nd phase constituents at micro and meso-scale have different local and global impact in bainitic multiphase steels. It is shown that earlier damage initiation and higher volume fraction of voids do not essentially lead to earlier macroscopic failure. Moreover, crystallographic orientations susceptible to damage initiation are identified by crystal plasticity modelling and experimentally validated by scanning electron microscopy observations.

Bainitic multiphase steels exhibit a positive strain rate sensitivity, which is desirable for crash worthiness and

for improving the forming behaviour.

It is shown that any microstructural strengthening mechanisms in steels can decrease the strain rate sensitivity.

The PhD research work of Behnam Shakerifard was carried out at Delft University of Technology in collaboration with Ghent University. Behnam Shakerifard successfully defended his PhD thesis on the 24th of June 2019. The title of his dissertation is ‘From Micro-mechanisms of Damage Initiation to Constitutive Mechanical Behaviour of Bainitic Multiphase steels’.

The thesis can be found at: https://repository.tudelft.nl/ islandora/object/uuid%3A230fffcb-b313-4f9f-bec0-e619bc62b0d4

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RESEARCH

Sustainable and functionalized inorganic binder-biofiber composites Annually 16 million m2 of so called wood wool composite boards (WWCB) are produced in Europe. Today, WWCB are made of wood wool strands, water and cement. WWCB are used in a wide range of applications, like thermal insulation, acoustic insulation, indoor decoration, etc. The material is still popular because their lightweight porous structure which makes them of interest as a filler providing thermal insulation and sound absorbing properties.

Furthermore the applied binding agent mineralizes the lignocellulose, adding high resistance to bio-degradation and fire. Nevertheless, there are disadvantages, like the necessarily use of fast setting and hardening of Portland cement (PC). The production of PC is contributing substantially to greenhouse gas emissions resulting in a search for alternative materials and the development of new binder types. In 2012 Guillaume Doudart de la Grée - Eindhoven University of Technology - started his PhD-research to study the performance based design and evaluation of lignocellulosic cement composite boards. Last year he defended his thesis successfully: ‘Development of sustainable and functionalized inorganic binder-biofiber composites’.

Wood wool cement boards (WWCB) are boards made of cement, wood wool and water. The product is known since 1900. After drying the wood, it is planed into long wood-wool strands - generally between 1 and 3 mm - in a wood wool machine. The strands are then mixed with the binding agent in a water solution, in a mixer. Wood wool boards which

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are bound with white cement are easily distinguishable by their beige colour.

First, Guillaume Doudart de la Grée studied the hydration kinetics of cements.

During production, many factors including storage conditions, used knives, recipes and material dosage, influence their properties. In general, moisture is in all stages a very influential parameter,

starting from the moisture content (Mc) of the wood logs. This influences not only the life time of cutting knives and energy consumption of the wood wool strands shredding machines, but also the dimensions of the produced wood wool strands. Therefore, it is recommended that the Mc of the wood-logs for board production is between 20-35 % based

RESEARCH on oven-dry wood. For the cement hydration, proper amount of water is of high importance, to obtain boards that can properly harden. The total water demand required for WWCB during the industrial production can be divided into:

• the moisture to reach the saturation •

• •

point of the used wood (30 % of the dry oven mass); the outer surface area of the wood wool strands (depending on the dimensions of the wood wool strands); the water demand required to let cement fully react (25 % of the mass of cement); the water demand to cover the surface of the cement particles.

Reducing carbon footprint

Next, the hydration kinetics of cements were studied and the retardation of sugars on cements with varying aluminate and CaSO4 contents are evaluated, providing new insights into the retardation mechanism. Based on the acquired knowledge, efficient utilization of binders through approaches including particle packing, modified mixing procedures and implementation of supplementary materials is investigated, leading to new WWCB with increased mechanical and thermal properties and reduced environmental footprints.

The use of alkali-activated binders is then studied to fully replace cement, based on the understanding of the alkaline degradation mechanism of wood and reaction mechanisms, which result in the development of a hybrid binder with a reduced carbon footprint of up to 60 % compared to the use of cement as binder and a significant reduction in costs.

Purifying the air

An orientated study is then performed on increasing the functionality of the boards by implementation of photocatalysis based on the fundamental insights in the surface morphology. Thus, the material was investigated to become an

air purifying material, adding an additional feature to this almost century old product. It was found that WWCBs had good support properties that allowed the use of very low quantity of TiO2, while realizing a high degradation rate (> 95 %). This increases not only the indoor air quality, but also makes the application of TiO2 for air purification also more cost efficient. This extraordinary performance was related to the high surface area while maintaining a high mass transfer due to the open surface structure. The TiO2 particles were homogeneously coated on a wider surface, allowing a greater efficiency, and thus higher degradation amount. Moreover, no intermediate compounds (NO2) were produced from the degradation of NOx.

Modelling and optimizing the sound absorption

The main application of WWCB is as a ceiling material because of its sound absorption properties. Hence, a study is performed to characterise the acoustic properties of WWCB manufactured with different strand widths, densities and board thicknesses. Using an impedance tube and optimized impedance models it was found that the acoustic performance of WWCB could be accurately predicted.

This enabled more inside into the sound absorption properties and allowed to specify regions of density, strand widths, thickness and even multilayer configurations in which the sound absorption was the highest.

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RESEARCH

Predicting the sound absorption; ‘performance based design’

Research summery

The PhD project of Doudart de la Grée was triggered to gain insight in the properties of WWCBs in order to make WWCB more sustainable by replacing cement with eco-friendly materials, broaden its functionality and improving/ understanding its properties. According to the researcher involved, the presented results positively indicated the achieve­ments and validity of the performed study.

Acknowledgements

Air purifying board; ‘functionality increase’

This work has been performed in close cooperation with prof.dr.ir. H.J.H. Brouwers (promotor from TU/e) and dr.

Qingliang Yu (co-promotor from Tu/e).

Furthermore, with the help of dr. Jan van Dam (Wagingen UR), Paul van Elten (Eltomation), dr.ir. Arno Keulen (former employe van Gansewinkel minerals), John van Eijk and Jan Mencnarowski all specialized on certain topics of this research. Special thanks to ir. Bram Botterman and ir. Veronica Caprai (former Msc students TU/e) with their personated involvement in experiments and discussion of findings. Finally, appreciation to all committee members, colleagues and friends which are mentioned in the thesis and contributed in their own way on this work.

Guillaume Doudart de la Grée

Sound absorbing panels of WWCB (Foto: BAUX)

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RESEARCH

(a) A demonstration house model of STPV-PDLC system. The window dimensions are around 10 * 5 cm. (b) The STPV-PDLC window reveals opaque in the ‘off’ state when no voltage is applied to the PDLC film. (c) The STPV-PDLC window turns semi-transparent when an AC voltage is applied to the PDLC film

Harvesting energy from your windows Globally, more than a third of energy consumption is attributable to the building sector. Reducing the consumption of building energy generated from fossil fuels helps alleviate the air pollution and global warming. Some European countries regulate that all new buildings shall be nearly zero energy buildings (ZEBs) by the end of 2020. Apparently, local energy harvesting is required to realize this goal. Among all realistic strategies, building-integrated photovoltaic (BIPV) is an obvious choice for those regions with adequate solar radiation. In congested urban areas, high-rise modern buildings possess more potential for harvesting solar energy around the window areas than roofs. Therefore, innovative design is required from the cell level to the system level regarding window-integrated photovoltaics.

Dr. Yuan Gao proposed, together with prof. Miro Zeman, prof. Kouchi Zhang, dr.

Olindo Isabella and dr. Jianfei Dong, an innovative approach to collecting solar energy from window areas in buildings and meanwhile creating comfortable daylighting. This idea is realized by designing and fabricating a semi-transparent photovoltaic (STPV) glazing window combined with a polymer-dispersed liquid-crystal (PDLC) film. The semi-transparent amorphous silicon solar cell shows an average transmittance of 20.04 % with a power conversion efficiency (PCE) of 6.94 %. According to the climate data of Delft, such a PCE is sufficient to power an equal-area PDLC film, which can switch from an opaque to a transparent state in a second by applying an alternating-current (AC) voltage. The prototype of a house model, containing

the STPV-PDLC system, has been built to demonstrate the feasibility of such a combination.

The PhD research work of Yuan Gao was performed under the joint supervision of Delft University of Technology in the Netherlands and State Key Laboratory of Solid State Lighting in China. Yuan Gao succeeded in defending his thesis on 25 June 2019, at Delft University of Technology. The title of his thesis is ‘Photovoltaic Windows: Theories, Devices and Applications’.

The thesis can be found at: https://doi.org/10.4233/ uuid:7aa8438c-6106-4c0f-a33f-0ceb8782ad23

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RESEARCH

Programmable soft actuators show the potential of soft robotics Researchers at TU Delft have developed highly programmable actuators that, similar to the human hand, combine soft and hard materials to perform complex movements. These materials have great potential for soft robots that can safely and effectively interact with humans and other delicate objects. The scientists reported their work in Materials Horizons, issue of July 8th, titled ‘Ultra-programmable buckling-driven soft cellular mechanisms’.

Robots are usually big and heavy. But scientists also want robots that can act delicately, for instance when handling soft tissue inside the human body. The field that studies this issue, is called soft robotics.

Owing to their soft touch, soft robotics can safely and effectively interact with humans and other delicate objects. Soft programmable mechanisms are required to power this new generation of robots.

Flexible mechanical metamaterials working on the basis of mechanical instability, offer unprecedented functionalities programmed into their architected fabric that make them potentially very promising as soft mechanisms. According to Shahram Janbaz, researcher and first

26 | INNOVATIVE MATERIALS 4 2019

RESEARCH higher modes of buckling and make the material predisposed to these higher modes.’

A conventional robotic arm is modified using the developed soft actuators to provide soft touch during pick-and-place tasks.

The article ‘Ultra-programmable buckling-driven soft cellular mechanisms; Materials Horizons, 8 July 2019; S. Janbaz, F. S. L. Bobbert, M. J. Mirzaali and A. A. Zadpoor (DOI 10.1039/c9mh00125e)’ is online> http://xlink.rsc.org/?DOI=c9mh00125e Contact: Jahram Janbaz S.Janbaz@tudelft.nl Amir Zadpoor A.A.Zadpoor@tudelft.nl TU Delft>

author, the tunability of the mechanical metamaterials proposed so far have been very limited.

The Delft-researchers presented some new designs of ultra-programmable mechanical metamaterials where not only the actuation force and amplitude but also the actuation mode could be selected and tuned within a very wide range. They also demonstrate some examples of how these soft actuators could be used in robotics, for instance as pick-and-place end-effector.

ling-driven materials is, however, contingent on resolving the main limitation of the designs presented to date, namely the limited range of their programmability. We were able to calculate and predict

Video

According to prof. dr. Amir Zadpoor, the function is already incorporated in the material’. ‘Therefore, we had to look deeper at the phenomenon of buckling,’ Zadpoor says on the website of Mechanical, Maritime and Materials Engineering (3mE), TU Delft. ‘This was once considered the epitome of design failure, but has been harnessed during the last few years to develop mechanical metamaterials with advanced functionalities. Soft robotics in general and soft actuators in particular could greatly benefit from such designer materials.

Unlocking the great potential of buck-

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INNOVATIVE MATERIALS 4 2019

Smart Materials, Part 4

Piezoelectrics: the working principle Smart materials are everywhere, but often invisible or simply not recognized. This is the fourth article in a series of eight, in which prof. Pim Groen will discuss the world of smart materials; this time piezoelectric materials, the working principle.

Piezoelectricity is the electric charge that accumulates in certain solid materials in response to applied mechanical stress and vice versa.

Pim Groen is professor of SMART Materials at Aerospace Engineering (AE) at Delft University of Technology (TU Delft) and Programme Manager of Holst Centre, TNO. 28 | INNOVATIVE MATERIALS 4 2019

INNOVATIVE MATERIALS 4 2019 Over the last editions the basics of piezoelectricity were discussed, starting with the materials and the equations to describe the mechanical and the electrical behaviour and the coupling between them. And just to remind: figure 1 shows the important graph which shows the strain versus the applied electrical field.

And notice: d is the piezoelectric charge constant (See Innovative Materials 3.)

First the piezo in the so-called d33 mode is observed (see figure 2). A piece of a piezoelectric material is poled in the 3 direction and an electric field is applied in the 3 direction. This is done by an uncontrained actuator so the stress is zero, another way of saying this is that the actuator can freely move. In this case now the strain is directly the d33 multiplied by the electric field.

The increase in thickness is directly d33 times the applied voltage.

Figure 3 shows the practica; modes of operation coupled.

If a piezo material is actuated in the 3 direction there is also strain in the 1 and in the 2 directions because the effect is coupled.

The ratio between the 1 and the 3 direction is given by the Poison’s ration which for a piezoceramic material is about 0.45. Please note the negative sign. A positive strain in the 3 direction gives a negative strain in the 1 direction.

The result is now that the volume of the piezomaterial is almost constant.

So what is the strain in the 1 direction?

Again this is done for an uncontrained situation (see figure 4), so no stress occurs. But now we must be carefull. The applied field is in the 3 direction. This field should be multiplied by the width over the thickness to calculate the strain the 1 direction.

Figure 1. Strain versus the electric field

Figure 2. Practical modes of operation: d33

Figure 3. Practical modes of operation: coupled

Figure 4: Practical modes of operation

29 | INNOVATIVE MATERIALS 4 2019

INNOVATIVE MATERIALS 4 2019 And now something completely different. In addition to the normal modes that is also a shear mode which can be used for actuation. Here the piezoelectric material is poled in the 3 direction and an electrical field is applied perpendicular to the poling direction so in the 1 direction.

To visualise this, figure 6 shows this strange looking cube. The cube represents a piezoelectric material. The poling direction is the arrow. And the electrodes on both faces can be seen.

When a voltage is applied over the electrodes, the material will deform.

And now again the strain for a free moving actuator can be calculated by the product of piezoelectric charge constant and the electric field. So S5 equals d15 multiplied by E1 (Figure 7).

Figure 5. practical modes of operation: shear

And is that all? No, there is also the hydrostatic mode. This one is used as microphone under water. It can detect changes in hydrostatic pressure.

A well known example here is the fishfinder which is based on this principle.

(Figure 8.)

The piezoelectric hydrostatic charge constant is given by d33 plus two times the d31.

Notice that for a Poison’s ration of 0.45 the dh is about 10% of d33.

Finally something about the transfer of energy between the electrical and mechanical domain. This is given by the electromechanical coupling coefficient k squared. This coupling coefficient represents the amount of mechanical energy which is transferred to electrical energy divided by the mechanical input energy.

And vice versa the electrical energy converted to mechanical energy divided by the electrical input energy.

Notice that k squared is not the efficiency of the system. There is no energy lost.

For PZT ceramics, our workhorse, in the d33 mode the value for k = 0.7 which means that k squared is 0.5.

Figure 6. Shear

Next time: piezoelectric actuators: the stack actuator and the bending actuator.

Figure 7. Practical modes of operation: shear

30 | INNOVATIVE MATERIALS 4 2019

INNOVATIVE MATERIALS 4 2019

Figure 8. Hydrostatic operation

Piezoelectric Materials and components A few years ago, Pim Groen, together with Jan Holterman, published ‘Piezoelectric Materials and components.’

It’s available online> An extended version (hard copy) can be ordered via the website of applied-piezo.com> Authors: Jan Holterman, Pim Groen ISBN: 978-90-819361-1-8 Hardcover, 218 fullcolor illustrations, 307 pages.

Figure 9. The electromechanical coupling coefficient

More info on the international edition is available on www.innovatievematerialen.nl

31 | INNOVATIVE MATERIALS 4 2019

ENTERPRISE EUROPE NETWORK

Enterprise Europe Network (EEN) supports companies with international ambitions The Enterprise Europe Network (EEN) is an initiative of the European Commission that supports entrepreneurs in seeking partners to innovate and do business abroad. The Network is active in more than 60 countries worldwide.

It brings together 3,000 experts from more than 600 member organisations – all renowned for their excellence in business support.

Database

Every company can participate by adjusting its profile to the database. This company will be brought to the attention in the country in which it wants to become active. At the same time it is possible to search for partners.

EEN advisers actively assist in compiling the profile, which is drawn up in a certain format. The EEN websites also contain foreign companies that are looking for Dutch companies and organizations for commercial or technological cooperation. The EEN advisers support the search for a cooperation partner by actively deploying contacts within the network. In addition, Company Missions

and Match Making Events are regularly organized. All these services are free of charge.

There are five types of profiles:

• Business Offer:

the company offers a product

Video: How Enterprise Europe Network works

• Business Request:

the company is looking for a product

• Technology Offer:

the company offers a technology

• Technology Request:

the company is looking for a technology

• Research & Development Request:

the organization seeks cooperation for research

When a company has both a Business Offer and a Business Request (or another combination), two (or even more if applicable) profiles are created.

The profile includes the most essential

information about the nature of the supply or demand, the ‘type of partner’ that is intended and the expected cooperation structure.

Get in touch with your local network contact point by selecting the country and city closest to where your business is based. They can help you with advice, support and opportunities for international partnerships.

For sustainable building and the creative industry, contact ir. drs. Hans Kamphuis: T: +31 (0) 88 042 1124 M: 06 25 70 82 76 E: hans.kamphuis@rvo.nl For Materials contact Nils Haarmans: T: +31 (0) 88 062 5843 M: 06 21 83 94 57 E: nils.haarman@rvo.nl More information websites can be found at the Europe Network websites: www.enterpriseeuropenetwork.nl http://een.ec.europa.eu

32 | INNOVATIVE MATERIALS 4 2019

ENTERPRISE EUROPE NETWORK The Enterprise Europe Network Materials Database: Request for partnership: September 2019.

Interested? contact hans.kamphuis@rvo.nl>

Eurostars: A French technological center and a French R&D performing SME are looking for SME partners to develop and refine altogether a novel polymer-derived ceramic based material for 3D printing.

An UK company and an European company are jointly seeking new technologies to facilitate the improved manufacturing and improve the functionality of polyolefins and polyols. The materials must have proof of concept and they should enable use in markets including construction, food, healthcare, automotive. Dependent on the stage of development the agreements may include licensing, joint venture, technical cooperation or commercial agreement with technical assistance.

A Bulgarian company is looking for suppliers of waste plastics

A Bulgarian company specialized in recycling waste plastics is looking for new suppliers from the European Union.

The company is offering supplier agreements.

A Korean SME seeking partners to cooperate development of coating materials and products for smart windows

A Korean SME is looking for partners to collaborate on a Eurotars2 project proposal. The project aims to develop and improve adhesive coating technology and display printing industrial technology in the field. Thus, the company is looking for partners related to energy efficiency in building by submitting a proposal of Eureka and Eurostars2 under research cooperation agreement.

Open-pored, dimensionally stable, flame retardant, lightweight board

Swiss company is looking for a board manufacturer - or a research & development partner, that produces, or develops, an open-pore, air-permeable, flame retardant, lightweight board. The board size is approximate 3.0 m x 1.2 m.

The product can be redeveloped or delivered as already existing board material. It will be used in the building industry.

The company seeks a partner for a manufacturing or a technical cooperation agreement possibly including development.

33 | INNOVATIVE MATERIALS 4 2019

ENTERPRISE EUROPE NETWORK The Enterprise Europe Network Materials Database: Request for partnership: September 2019.

Interested? contact hans.kamphuis@rvo.nl>

Thermal insulation technologies sought for electric vehicle battery pack housing

A Spanish (Catalan) company specialised in design and manufacture of thermal, thermo-acoustic and electromagnetic insulations for automotive industry, is looking for technologies to thermally insulate the battery pack housing to optimize the performance of electric vehicles batteries and guarantee the protection of the passengers in case of thermal runaway inside the battery. The company is looking for collaboration in the form of research cooperation, technical cooperation or license agreement.

Czech SME seeks a manufacturer or a supplier of polymer textile with good moisture transfer capability under supplier agreement

A Czech SME developed and sells period panties with special nanofiber absorbent layer. Now they are searching for the polymer textile manufacturer or supplier that would supply one part of this absorbent layer under supplier agreement. The key variable of the textile is the moisture transfer capability. Textile should be delivered in roles and doesn’t require additional processing or adjustment before the delivery.

Voeg informatie toe aan de Kennisbank Biobased Bouwen De Biobased Economy speelt een belangrijke rol in de duurzame ontwikkeling van Nederland en biedt nieuwe kansen voor het bedrijfsleven. Via de kennisbank kunt u kennis vergaren en delen over de beschikbaarheid en toepassingsmogelijkheden van biobased materialen, producten en bouwconcepten. Samen versterken we zo de biobased economie.

Ruim dertig partijen in de bouwsector ondertekenden de green deal biobased bouwen. Deze producenten, architecten, adviseurs en kennisinstellingen delen hun kennis rond kansrijke mogelijkheden van biobased bouwen. Ook de ministeries van Binnenlandse Zaken (Wonen en Rijksdienst), Economische Zaken, en Infrastructuur en Milieu ondersteunen de green deal.

Bouw ook mee aan de biobased economie en voeg uw project- of productbeschrijvingen toe aan deze kennisbank.

34 | INNOVATIVE MATERIALS 4 2019 Kijk op www.biobasedbouwen.nl voor meer informatie>

25-26 SEPTEMBER

21E EDITIE

Kunststoffen oven h d l e V , f 2019 o h s ng re t n Ce e c n e fer

9.30-17.00 uur

i

n Ko

on C H

N

Ervaar alles op het gebied van: • Duurzaamheid en recycling • Kostprijs-besparing • Innovatieve productiemethodes • Productontwikkeling • Slimme materialen • Automatisering in de kunststoffenbranche

Gratis toegang Meld u direct aan via www.kunststoffenbeurs.nl

Laat u inspireren en verrassen door de waardevolle ontwikkelingen en mogelijkheden binnen de kunststofwereld. Ontmoet productontwerpers, gereedschapsmakers, grondstofleveranciers, spuitgieters, extrudeurs, vacuümvormers en machineleveranciers.

De Kunststoffenbeurs is ook dit jaar weer uniek!

www.kunststoffenbeurs.nl

an g r O

ie: t a is

EVENTS Stainless & Speciality Steel 17 - 19 September 2019, Sevilla

K 2019 16 - 23 October 2019, Düsseldorf

Werkstoff woche 2019 18 - 20 September 2019, Dresden

Dutch Design Week 2019 19 - 27 oktober 2019, Eindhoven

Kunststoffen 2019 25 - 26 September 2019, Veldhoven

Advanced Building Skins 28 - 31 October 2019, Bern

European Symposium on Biopolymers 25 - 27 September 2019, Straubing

Betondag 2019 14 November 2019, Rotterdam

EFIB 2019 30 september - 2 October 2019.

Brussel

Biocomposites 14 - 15 November 2019, Keulen

Lijmen 2019 1 October 2019, Veldhoven

Greenbuild 2019 19 - 20 November 2019, Atalanta

Schweissen 2019 1 - 3 October 2019, Linz

Formnext 19 - 22 November 2019, Frankfurt

Solids Rotterdam 2019 2 - 3 October 2019, Rotterdam

Glass industry fair 20 - 23 November 2019, Poznan

Metavak 8 - 10 October 2019, Gorinchem

European Aluminium Congress 2019 25 - 26 November 2019, Düsseldorf

ISPA 2019 9 - 10 October 2019, Dresden

GlassPrint 2019 Conference 27 - 28 November 2019, Düsseldorf

Euro PM 2019 13 - 16 October 2019, Maastricht

European Bioplastics Conference 2019 3 - 4 December 2019, Berlin

Holz 2019 15 - 19 October 2019, Basel

Meeting Materials 2019 12 december 2019, Noordwijkerhout

36 | INNOVATIVE MATERIALS 4 2019

http://hightechmaterials.4tu.nl

Select key words and find relevant materials scientists or research groups within 4TU.

High-Tech Materials form the key to innovative and sustainable technology

www.4tu.nl/htm @4TU_HTM

4TU.HTM Research Programme New Horizons in Designer Materials | Visibility and accessibility of Materials Science & Engineering | Annual symposium Dutch Materials | 4TU.Joint Materials Science Activities | web application http://hightechmaterials.4tu.nl

Innovative Materials, the international version of the Dutch magazine Innovatieve Materialen, is now available in English. Innovative Materials is an interactive, digital magazine about new and/or innovatively applied materials.

Innovative Materials provides information on material innovations, or innovative use of materials. The idea is that the ever increasing demands lead to a constant search for better and safer products as well as material and energy savings. Enabling these innovations is crucial, not only to be competitive but also to meet the challenges of enhancing and protecting the environment, like durability, C2C and carbon footprint.

By opting for smart, sustainable and innovative materials constructors, engineers and designers obtain more opportunities to distinguish themselves.

As a platform Innovative Materials wants to help to achieve this by connecting supply and demand.

Innovative Materials is distributed among its own subscribers/network, but also through the networks of the partners. In 2019 this includes organisations like M2i, MaterialDesign, 4TU (a cooperation between the four Technical Universities in the Netherlands), the Bond voor Materialenkennis (material sciences), SIM Flanders, FLAM3D, RVO and Material District.