A comparative study of tool wear behavior for PVD coatings with different functional layers

To maximize the wear resistance of high-performance cutting tools, hard coatings are applied by using Physical Vapor Deposition (PVD). Beyond the specific cutting conditions, the coating composition and the resulting coating properties are decisive factors influencing the performance of the cutting tool. This paper investigates the effects of different functional layers and the resultant coating properties on the wear behavior of the cutting tools during turning of C45+N steel. Therefore, cutting tools based on WC-Co substrate with 6 wt.% Co are coated with TiAlCrN, TiAlSiN, and TiAlCrSiN. A comprehensive coating characterization was conducted, including the measurement of residual stresses by focused ion beam combined with digital image correlation. The coated tools were used in turning experiments to determine the tool wear behavior of the different coatings. Among the coatings the TiAlCrN coating demonstrated the longest tool life. This study aims to establish a connection between coating properties with a focus on the residual stresses and wear behavior of different coating compositions.