Surface Properties of (Cr,Al,Si)N Films Synthesized by RF Magnetron Sputtering Method

Abstract

Because of their high hardness, wear resistance, corrosion resistance, and oxidation resistance, Cr_XAl_YN protective coatings with differing X and Y values are used widely for cutting tools, slide members, and mechanical components. To enhance these properties further, Si atoms were incorporated to Cr_XAl_YN with metal ratios close to the phase boundary separating cubic and hexagonal phases. The Cr_XAl_YSi_ZN maintained its NaCl-type cubic structure without hexagonal phase segregation. The maximum value of microhardness was 38 GPa at Z＝0.14, where a lower friction coefficient was obtained because abrasion progression was prevented. Thermogravimetric analyses showed that oxidation resistance at 800-1000 ℃ was improved by increasing the Si contents. The flank wear of Cr_XAl_YSi_ZN-coated cutting tools was lower than that of non-coated tools. This paper presents surface properties such as microstructure, microhardness, tribological properties, oxidation resistance, and tool wear behaviors of Cr_XAl_YSi_ZN synthesized from alloy targets using radiofrequency magnetron sputtering.