Cast base for biomedical use formed of cobalt-chromium based alloy and having excellent diffusion hardening treatability, sliding alloy member for biomedical use and artificial joint

Abstract

A cast base for biomedical use, which is formed of a cobalt-chromium based alloy and has excellent diffusion hardening treatability, characterized by containing 0.1 mass % or greater of nitrogen (N) and having a volume fraction of an fcc (face centered cubic lattice) phase in the metallic structure thereof of 50% or greater. Even in the case of subjecting the aforesaid cobalt-chromium based alloy cast base in the as-cast state, the structure of which is liable to be non-uniform, to a diffusion hardening treatment, it is possible to obtain a sliding alloy member for biomedical use, wherein a uniform hardened layer has been formed, by the diffusion hardening treatment. Thus, a sliding alloy member for biomedical use and so on, which can stably and continuously exhibit high strength, excellent abrasion resistance and, moreover, excellent corrosion resistance, can be provided.

Dependencies are inferred from the claim text.