SURFACE COATED CUTTING TOOL WITH HARD COATED LAYER EXHIBITING EXCELLENT CHIPPING RESISTANCE

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cutting tool with a hard coated layer exhibiting excellent chipping resistance in high speed heavy cutting machining. SOLUTION: A lower part layer is constituted of (a) a titanium carbonitride layer, (b) a Ti-Cr composite carbonitride layer an inclusion ratio of chrome of which is 0.01-0.1 (atomic ratio) and a Ti system compound lamination layer constituted by alternately laminating the above (a) and (b), an upper part layer is constituted of (c) a two-phase mixed oxide layer of aluminum oxide and zirconium oxide an inclusion ratio of zirconium of which is 0.1-0.2 (atomic ratio) and additionally, the Ti-Cr composite carbonitride layer of the above (b) is constituted of the Ti-Cr composite carbonitride layer in which the highest peak exists inΣ3 in a constitutive atom covalent lattice point distribution graph formed in accordance with a measuring result of an inclination made by a normal of a (001) face and a (011) face of a crystal grain existing in a measuring area of a surface polishing face and a normal of the surface polishing face and a distribution rate ofΣ3 occupying in the whole ofΣN+1 is more than 60%. COPYRIGHT: (C)2008,JPO&INPIT