Coatings for high-temperatures uses with tribological stress
The present invention relates to a coating for high-temperature uses with tribological stress. The coating comprises a multi-layer system and a top lubricant layer, the top lubricant layer containing molybdenum as a main component.
1. Coating with a multi-layer coating system and a top smear layer, wherein the multi-layer coating system contains at least one HT layer and the top smear layer has a composition according to Mo a —X b —Y c , wherein a, b and c indicate the atomic concentration of the respective components, and a+b+c=1, and 0≦b<a and 0≦c<a, with X being the variable metal component: B, Si, V, W, Zr, Cu and Ag or a combination thereof, with Y as variable non-metallic component: C, O and N or a combination thereof, wherein the multi-layer coating system comprises at least one actively lubricating layer, characterized in that the at least one actively lubricating layer is a Ti—Al—Mo—N layer that has an averaged Mo content when measured by EDX at 10 kV of 20-60 mat %.
2. Coating according to claim 1 , wherein the actively lubricating layer has an averaged Mo content when measured by EDX at 10 kV of 25-35 at %.
3. Coating according to claim 1 , wherein the actively lubricating layer has an averaged Mo content when measured by EDX at 10 kV of 30 at %.
4. Coating according to claim 1 , characterized in that the at least one actively lubricating layer is formed of nano-layers with MoN-rich nano-layers and nano-layers poor in MoN.
5. Coating according to claim 4 , characterized in that the thickness of the MoN-rich nano-layers are between 10-60 nm.
6. Coating according to claim 5 , wherein the thickness of the MoN-rich nano-layers are between 20-50 nm.
7. Coating according to claim 5 , wherein the thickness of the MoN-rich nano-layers are between 30-40 nm.
8. Coating according to claim 5 , wherein the thickness of the MoN-rich nano-layers are 40 nm.
9. Coating according to claim 4 , characterized in that the MoN-rich nano-layers are between 20-50 nm.
10. Coating according to claim 4 , characterized in that the MoN-rich nano-layers are between 30-40 nm.
11. Coating according to claim 4 , characterized in that the MoN-rich nano-layers are 40 nm.