CUTTING TOOL MADE OF SURFACE COATED CEMENTED CARBIDE WITH HARD COATING LAYER EXHIBITING EXCELLENT WEAR RESISTANCE UNDER HIGH-SPEED HEAVY CUTTING CONDITION

摘要

PROBLEM TO BE SOLVED: To provide a cutting tool made of surface coated cemented carbide with a hard coating layer exhibiting excellent wear resistance under high-speed heavy cutting conditions. SOLUTION: The cutting tool made of surface coated cemented carbide is formed by physically depositing the hard coating layer made of a composite nitride of Ti, Al and Si by a total average layer thickness of 1 to 10μm on a surface of tungsten-carbide-based hard metal substrate or a titanium-carbonitride-based cermet substrate. The hard coating layer has the maximum Al content points and the maximum Ti content points alternately and repetitively present with predetermined intervals in the thickness direction and has a component concentration distribution structure where the Al and Si contents and further the Ti content continuously vary between both points respectively. Moreover, the maximum Al content point satisfies a composition formula of (Al1-(X+Y)SiXTiY)N where X is 0.20 to 0.35, Y is 0.10 to 0.30 in atomic ratio, and the maximum Ti content point satisfies a composition formula of (Ti1-(M+Z)AlMSiZ)N, respectively, where M is 0.05 to 0.25, and Z is 0.01 to 0.15 in atomic ratio. The distance between the adjacent maximum content points of Al and Ti is 0.01 to 0.1μm. COPYRIGHT: (C)2004,JPO&NCIPI