Influence of DC Bias Voltage on Structure and Performance of the Al-Cr-Si-N Coatings Prepared by Arc Ion Plating Technique

Al-Cr-Si-N coatings were deposited by an arc ion plating (AIP) technique at various DC bias voltages. The effects of bias voltage on the microstructure, phase composition, mechanical and wear properties of the Al-Cr-Si-N coatings were investigated. The results show that the AI-Cr-Si-N coating is mainly composed of the hexagonal structure and the face-centered cubic structure of AIN phase. With the increase of substrate bias, the diffraction peak of the coating shifts to the small angle, and compressive stress gradually increases, whose maximum value is -0.77 GPa; however, the hardness and friction coefficient of the coating do not change significantly. When the negative bias of the substrate is -40 V, the characteristic parameters HIE and H-3/E-*2 of the Al-Cr-Si-N coating reach the maximum values of 0.15 and 0.37 GPa, respectively. At the same time, the coating has the best wear resistance and the lowest friction coefficient.