Effect of cathode arc current and bias voltage on the mechanical properties of CrAlSiN thin films

Abstract

Thin films of CrAlSiN were deposited on SKD 11 tool steel substrate using Cr and AlSi cathodes by a cathodic arc plasma deposition system. The influence of AlSi cathode arc current and bias voltage on the mechanical and the structural properties of the films were investigated. The CrAlSiN films have a multilayered structure in which the nano-crystalline CrN layers alternate with nano-amorphous AlSiN layers. The hardness of the film increased with the increase of aluminum-silicon cathode arc current from 35 A to 50 A. Further increases in the current decreased the hardness. The maximum hardness of 42 GPa was obtained at the current of 50 A. The hardness of the film increased with the increase of the bias voltage up to −100 V. Further increases in the bias voltage decreased the hardness of the films. The period of the film decreased with the increase of the bias voltage. The maximum hardness was observed with the films deposited at the bias voltage of −100 V.