SURFACE COATED CEMENTED CARBIDE CUTTING TOOL WITH HARD COATING LAYER EXHIBITING EXCELLENT CHIPPING RESISTANCE IN HIGH-SPEED HEAVY CUTTING CONDITION

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cemented carbide cutting tool with a hard coating layer exhibiting excellent chipping resistance in high-speed heavy cutting conditions. SOLUTION: This surface coated cutting tool is formed by physical vapor deposition of the hard coating layer comprising a compound nitride layer of Ti, Al and Zr, in the average layer thickness of 1-15μm on the surface of a tungsten carbide group cemented carbide substrate. The hard coating layer has a component concentration distribution structure wherein maximum Al content points and minimum Al content points exist in alternate repetition at predetermined spaces along a layer thickness direction and the Al component content rate continuously changes from the maximum Al content point to the minimum Al content point, and from the minimum Al content point to the maximum Al content point, and the maximum Al content point satisfies a composition formula: (Ti1-(X+Y)AlXZrY)N, and the minimum Al content point satisfies a composition formula: (Ti1-(X+Y)AlXZrY)N, and further the spacing of the adjacent maximum Al content points and minimum Al content points is 0.01-0.1μm. COPYRIGHT: (C)2005,JPO&NCIPI