| 摘要 |
PROBLEM TO BE SOLVED: To obtain a coated cermet having high adhesion to a hard coating layer by providing a W-enriched layer, having W quantity larger than that of the inner part of a TiCN-base cermet, to the vicinity of the base material composed of the cermet, at the time of providing the hard coating layer to the surface of the base material composed of the TiCN-base cermet. SOLUTION: A TiCN-base cermet, having a composition represented, e.g. by TiCN-16%WC-12%Co-4%Ni-8%TaC, is sintered by the ordinary powder metallurgy method. The resultant sintered cermet is ground into a shape of a throw away tip for face milling cutter and subjected to reheating treatment at about 1350 to 1500 deg.C in a pressure sintering furnace, and a TiAlN hard coating layer is formed by means of the known PVD to about 3μm thickness by using the alcove sintered cermet as a base material. By this method, a W- enriched layer, having W quantity larger by >= about 20% than that of the innert part of the cermet, is formed in the vicinity of the surface (in the part at a depth of <= about 20μm from the surface) of the base material composed of the cermet, and the coated cermet excel lent in toughness and capable of withstanding long use can be obtained.
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