CUTTING TOOL MADE OF SURFACE COATED CEMENTED CARBIDE HAVING COATED LAYER EXHIBITING EXCELLENT CHIPPING RESISTANCE IN HIGH-SPEED CUTTING WORK OF HARD-TO-CUT MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a cutting tool made of surface coated cemented carbide having a coated layer exhibiting excellent chipping resistance in high-speed cutting work of hard-to-cut material.;SOLUTION: In this cutting tool made of surface coated cemented carbide, a hard coated layer formed by following (a) and (b) is formed on the surface of a tungsten carbide-base cemented carbide base body or a titanium carbide nitride-base cermet base body: (a) A lower layer formed of (Ti, Al)N layer having an average layer thickness ranging from 1 to 5 μm, in which Al maximum content point and Al minimum content point alternately exist repeatedly at predetermined intervals in the direction of layer thickness, Al and Ti contents respectively continuously change, the Al highest and lowest containing points satisfy a specific composition formula, and the interval between the adjacent Al maximum and minimum content points ranges from 0.01 to 0.1μm; (b) an adhesive bonding layer formed of CrN layer having an average layer thickness of 1 to 5 μm; and (c) an upper layer formed of Cr dispersed Cr₂O₃ layer having the structure in which metal Cr is dispersed ad distributed in the base of Cr₂O₃.;COPYRIGHT: (C)2007,JPO&INPIT