Hard dense CrNx coatings on three-dimensional objects

Thin CrNx coatings were deposited on steel in an industrial, Hauzer HC 750 PVD machine equipped with a bucket plasma source. The microstructure, deposition rate and chemical composition of the deposited coatings all depend on the applied bias voltage, the nitrogen flow and the deposition temperature. The results show a constant high hardness and Youngʹs modulus for applied bias voltages above 50 V. Remarkably, the composition of the coating has only a small influence on the hardness and modulus. It was found that high hardness and high density correlate very well.