Patent ID: 8012611

Claim:
A surface-coated cutting tool comprising a substrate and a coating formed on said substrate, wherein said coating includes a first coating of TiCN and a second coating of α-type Al 2 O 3 , said first coating is located between said substrate and said second coating, and said second coating has compressive stress S 1 in an area A 1 spreading from an insert ridge portion in the direction of a rake face and the direction of a flank face with distances of at least 0.5 mm respectively and has tensile stress S 2 in an area A 2 other than said area A 1 , while said compressive stress S 1 and said tensile stress S 2 are defined by the following expression (I): 400 Mpa≦| S 1− S 2|≦3500 MPa (I).