Surface-coated cutting tool member having hardcoating layer and method for forming hard coating layer on surface of cutting tool

摘要

A surface-coated cutting tool member exhibiting a superior tool life due to a hard coating layer thereof is provided. The surface-coated cutting tool member includes a tungsten carbide based cemented carbide substrate, a titanium carbonitride based cermet substrate, or a cubic boron nitride based sintered substrate; and a hard coating layer of a nitride compound containing titanium and yttrium, which is formed on a surface of the substrate using a physical vapor deposition method in an overall average thickness of 1 to 15 mum. The hard coating layer has a component concentration profile in which maximum Y component containing points (minimum Ti component containing points) and points without Y component (TiN points) appear alternatingly and repeatedly at a predetermined interval in a direction of thickness of the hard coating layer, and the amount of contained Y component is continuously changed from the maximum Y component containing points to the points without Y component and from the points without Y component to the maximum Y component containing points, the maximum Y component containing points satisfy a composition formula of (Ti_1-XY_X)N (where X indicates an atomic ratio of 0.005 to 0.15), and a distance between one of the maximum Y component containing points and adjacent one of the points without Y component is from 0.01 to 0.1 mum.