Patent ID: 8003234

Claim:
A coated cutting insert comprising: a substrate; a base layer formed on said substrate; and an indicating layer formed on a part of said base layer; wherein said substrate has at least one surface serving as a rake face and other at least one surface serving as a flank face, the rake face and the flank face continue to each other with a cutting edge lying therebetween, said base layer exhibits a color different from that of said indicating layer, said indicating layer is formed on said flank face, on said base layer on an entire surface or a part of a region A 2 except for a region A 1 extending from said cutting edge with a width of at least 0.2 mm to less than 4.0 mm, and on said rake face, on said base layer on an entire surface or a part of a region B 2 except for a region B 1 extending from said cutting edge with a width of at least 0.2 mm to less than 4.0 mm, in said region A 1 and said region B 1 , said base layer is exposed at a surface, and at least one layer constituting the exposed base layer has compressive residual stress in one or both of said region A 1 and said region B 1 , and said compressive residual stress is stress of which absolute value is at least 0.1 GPa.