Patent ID: 7601440

Claim:
A hard coating excellent in wear resistance and oxidation resistance and made by stacking a layer A and a layer B that have different compositions, wherein the layer A is one selected from a group consisting of: (1) a hard coating having composition of (Al a ,Cr 1-a )(C 1-e N e ) satisfying the relations: 0.25 ≦a≦ 0.7 and 0.5 ≦e≦ 1; (2) a hard coating having composition of (Al a ,Si c ,B d ,Cr 1-a-c-d )(C 1-e N e ) satisfying the relations: 0 <c+d≦ 0.2, and 0 <c+d≦ 0.2, and 0.5 ≦e≦ 1; and (3) a hard coating having composition of (Al a ,Si c ,B d ,Ti 1-a-c-d )(C 1-e N e ) satisfying the relations: 0.25 ≦a≦ 0.7, 0 <c+d≦ 0.15, and 0.5 ≦e≦ 1; (where a, c, d and e that represent atomic ratios of Al, Si, B and N, respectively) and the layer B is a hard coating having composition of (M b ,Si c ,B d )(C 1-e N e ) where M represents W and/or Mo, satisfying the relations: 0.8 ≦b≦ 1, and 0 ≦c+d≦ 0.2; (where b, c, d and e that represent atomic ratios of M, Si, B and N, respectively) wherein the layer A and the layer B are stacked one on another so as to satisfy the following relation (1): 0.5 (nm)≦(Thickness of layer B)≦(Thickness of layer A) (1).