Study of Interlayer Element Effect on Properties of AlCrTiSiN Thin Film

Abstract

In this work, the effect of different interlayer elements on the properties of the top AlCrTiSiN film, i.e. titanium and chromium called as Ti/AlCrTiSiN and Cr/AlCrTiSiN, respectively, was studied. The film was deposited by cathodic arc physical vapor deposition on tungsten carbide (WC) specimen which is extensively used as cutting tools material. Various properties including the surface hardness, the scratch resistance and tribological performance were later studied. The surface hardness of both Ti/AlCrTiSiN and Cr/AlCrTiSiN coatings were higher than 29 GPa. The critical load for both coating suggesting supurb adhesion strength of the coating system. However, Ti interlayer was found to result in higher critical compressive stress for first damage and full delamination at room temperature. The wear resistance of coated specimens was far better than the uncoated one both at room temperature and high temperature, i.e. ball on disc tests at room temperature, 300 °C, and 500 °C were performed. The coeeficient of friciton of both coatings were found to depend strongly on the wear behavior of the system and the characters of the wear debris. A sign of better tribological performance at high temperature, i.e. 500°C, could be noticed with Cr interlayer as the lower mismatch in coefficient of thermal expansion became more crucial in film damage phenomina at such temperature.