PROBLEM TO BE SOLVED: To improve a wear resistance by providing a Tin and/or TiCN layer as an inner layer in the surface of a specified sintered hard alloy as a base body, Ti carbide, a nitride and a carbonitride as a middle layer and an Al oxide and/or Ti nitride and a carbon nitride as an outer layer. ;SOLUTION: For a base body, a sintered hard alloy made of one or more selected from the group of 4a to 6a carbide, nitride and carbonitride and one or more selected from the group of Fe, Ni, CO, W, Mo and Cr is used, and a Tin and/or TiCN layer as an inner layer is provided in the surface of this base body. A middle layer is formed by using one or two more particles selected from Ti carbide, a nitride and carbon nitride and an outer layer is formed by using one or two more selected from Al oxide and/or Ti nitride and carbonitride. In this case, since a film is made thicker for turn-machining and its grain size is made particle, by using this small grain size thick film, a wear resistance is provided to the outer layer.;COPYRIGHT: (C)1997,JPO
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