In recent years, high entropy alloys have attracted increasing scientific interest not only as a material class for high-temperature applications but also as a promising material class for thin-film applications. Nitride hard coatings based on high entropy alloys share many positive properties with their metallic counterparts, such as high strength or high thermal stability.

In the following contribution, results on the deposition of different high entropy nitrides (HEAN) are presented. The hard coatings were produced by cathodic vacuum arc deposition. The influence of different substrate biases and working pressures on the coating microstructure and mechanical properties were investigated via SEM, TEM, XRD and nanoindentation.

All coatings displayed a single-phase fcc (NaCl) microstructure with more or less pronounced columnar grain growth. For individual coatings, high hardness close to 40 GPa was observed. The high hardness is most likely correlated to a pronounced grain refinement effect at high subtrate bias.

From a current perspective, HEAN display great potential for industrial application as hard coatings under severe thermomechanical loads.