Coating Features Decreasing Internal stress
Hardness
Wear resistance (abrasive)
Wear resistance (oxidation)
Hot hardness
Heat insulation
Max. usage temperature
Possibility of thickness increase
Decreasing friction
Possibility of Nanocomposite
TiCN typically TiAlCN with Al~20-25% typically TiAlN typically AlTiCrN
Grain fineness
Ti+N=TiN Basic coating
+ Component
Coating
Low target costs with alloyed targets Low target costs with unalloyed targets LARC
Influence of the Most Important Component Materials on Coating's Features
+N +C
0 0
--
+ ++
+ ++
+ -
0 -
0 --
0 -
--
0 ++
no no
0 0
0 0
+ Al
(+)
+
-
-
+
+
+
+
+
-
no
--
0
+Al / (-C) +Cr
+ -
+
+ if Al<X% / - if Al>X% +
+ +
+ +
+ +
++ +
+ (+)
+
-
no no
-
+ (-)
+
(+)
++
(+)
+
+
(+)
+
(-)
no
--
-
(+)
++
+
++
++
++
++
0
0
yes
--
+
typically AlCrN +Cr / (-Ti) -Cr~30% typically TiAlN/SiN +Si ++ CrAlN/SiN, AlCrTiN/SiN
+ means mainly positive change in the user's point of view
X is approximately around 65%
Critical Loads at Scratch Test First crack
250
First Crack, Lc2 [N] Delamination, Lc3 [N]
200
188.4
188.3
150
150
89.1
100
102.1
90.6
60
End of crack: partial delamination
50 0
Hardness
200
183.4
Conventional PVD Coating
97.9
no visible delamination at 200N
Adhesion
- means mainly negative change in user's point of view
nACo2® nACo2®-MLH nACo2®-Si+ nACRo2® Gradient Gradient Gradient Average values from min. 10 measurements with deviation; <5% Scratch length: 70 mm - scratch speed: 0.4 - 60 mm/min Measured on tungsten carbide K40, by CSEM, Neuchâtel, Switzerland
Absorption of Cracks by Multilayer Structure Indentor
Film cr
Substrate 300
Hardness = F/d [GPa]
load [mN]
250 200 150 100 50 0
0
50
100
150
200
displacement [nm]
250
300
Source: TOPNANO-Project, EPF Lausanne, Switzerland Measuring hardness by nanoindentation
91