Patent ID: 7396597
Filing Date: 2008-07-08
Classification: C22C,Y10T

Abstract:
1. A Ni—Cr—Fe alloy for use in a carburizing gas atmosphere comprising a base metal having a chemical composition comprising in mass %, C: 0.01-0.6%, Si: 0.1-5%, Mn: 0.1-10%, P: at most 0.08%, S: at most 0.05%, Cr: 22-55%, Ni: 23-70%, N: 0.001-0.25%, O: oxygen: at most 0.02%, and a remainder of Fe and impurities, the base metal having in its surface region a Cr-depleted zone with a Cr concentration of at least 10 mass % but less than a concentration of Cr in the base metal, and a thickness of at most 20 micrometers, said surface of the base metal formed by removing an oxide scale generated by heating of the base metal.