Patent ID: 7601389
Filing Date: 2009-10-13
Classification: B22C,C22C,C23C,Y10T

Abstract:
1. A method of producing a metal material comprising a diffusion layer which is formed by diffusing an element into a base material of a metal and which has a depth from a surface of said base material of not less than 0.5 mm, a concentration of said element being gradually decreased from said surface to inside of said base material, said method comprising: coating said surface of said base material with a coating agent, said coating agent consisting essentially of a powder of a substance containing said element to be diffused, a reducing agent for reducing an oxide film formed on said surface of said base material, and a solvent in which said powder of said substance and said reducing agent are dispersed or dissolved; and diffusing said element into said base material by heating said base material which is coated with said substance such that the element is diffused into the base material to a depth of not less than 0.5 mm from the surface, wherein said diffusing step causes the concentration of said element to be gradually decreased from said surface to inside of said base material such that an interface is not formed between the base metal material and the diffusion layer, and the surface of the base metal material having the element diffused therein is exposed outwardly after said diffusion step.