The surface coating cutting tool null tungsten carbide basis which shows the resistance abrasiveness where hard

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cutting tool having a hard coating layer exhibiting excellent wear resistance in high-speed heavy cutting of difficult-to-cutting material.;SOLUTION: The hard coating layer of the surface coated cutting tool is composed of an upper layer and a lower layer formed by chemical vapor deposition. The upper layer is composed of an aluminum oxide layer having the average layer thickness of 1 to 15 μm, and the lower layer is composed of a close adhesive Ti compound layer, and a modified Ti based carbonitride layer having the total average layer thickness of 3 to 20 μm. The modified Ti based carbonitride layer has the average layer thickness of 2.5 to 15 μm, and is composed of: a matrix phase composed of complex carbonitride of Ti and Cr satisfying (Ti_1-x Cr_x) CN (where: X=0.05 to 0.15) formed by heat treatment after vapor deposition; and a complex carbonitride precipitated phase of Ti and Cr satisfying (Ti_1-Y Cr_Y) CN (where: Y=0.2 to 0.8) and continuously precipitated in the crystal grain boundary.;COPYRIGHT: (C)2008,JPO&INPIT