Non-ferrous metal mechanical part
AssigneeKabushiki Kaisha Toshiba
InventorsTakashi Ishii, Hisao Yabe, Hajime Kohama
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Abstract
A non-ferrous metal mechanical part having a wear-resistant and smooth surface, and comprising a substrate of a metal selected from the group consisting of aluminum, aluminum alloy, nickel, and nickel alloy, and a surface layer formed on a surface of said substrate and containing chromium oxide (Cr.sub.2 O.sub.3) as a major constituent. The chromium oxide (Cr.sub.2 O.sub.3) is a substance which has been converted by heating a chromium compound, and an intermediate layer containing a reaction product between the substrate and chromium oxide in the surface layer is formed at an interface between the surface layer and the substrate.
Claims11
A non-ferrous metal mechanical part having a wear-resistant surface comprising:
- (a) a substrate of a metal selected from the group consisting of aluminum, aluminum alloy, nickel and nickel alloy;
- (b) a substantially non-porous surface layer formed on a surface of said substrate, said surface layer substantially containing chromium oxide, said chromium oxide being converted from a chromium compound capable of forming the same upon heating thereof;
- and
- (c) an intermediate layer including a reaction product between the chromium oxide in said surface layer and said substrate, being formed at an interface between said surface layer and said substrate;
- which mechanical part is produced by a process which comprises:
- (1) applying an aqueous solution of a chromium compound capable of forming chromium oxide upon heating to the surface of a substrate of a metal selected from the group consisting of aluminum, aluminum alloy, nickel and nickel alloy, to form a coated substrate;
- and
- (2) heating said coated substrate to a temperature of about 450.degree. to 600.degree. C., thereby converting said chromium compound in said applied aqueous solution to chromium oxide, to form a dense, hard wear-resistant ceramic layer on said substrate.
Dependencies are inferred from the claim text.