Synthesis of nano-structured HPPMS CrN/AlN coatings

Nanolaminates are promising coating architectures for tools and components subjected to high loads. Due to the possibility to reach high hardness and low indentation modulus by reason of a superlattice effect or the formation of a solid solution crystallite these types of coatings are widely discussed in the literature. Furthermore, a nanolaminate structure allows simple process design for industrial applications. In this paper high-power pulse magnetron sputtering (HPPMS) was used to deposit CrN/AlN nanolaminates with different bilayer periods by varying the rotational speed of the substrate holders. For bilayer periods of 4.5 nm and a resulting theoretical AlN single layer thickness of about 1.7 nm a hardness of 27.4 GPa can be reached.