Patent ID: 7875128
Filing Date: 2011-01-25
Classification: C21D,C22C,C23C

Abstract:
1. A method for manufacturing a nickel-free stainless steel product from a nickel-free ferritic stainless steel material, with a part thereof being austenitized, the method comprising the steps of: cold-rolling said nickel-free ferritic stainless steel material containing 18 to 24% by mass of Cr and 0 to 4% by mass of Mo; subjecting said nickel-free ferritic stainless steel material to a nitrogen absorption treatment to allow said nickel-free ferritic stainless steel material to contain 0.3 to 1.5% by mass of N; austenitizing a part of said nickel-free ferritic stainless steel material; and removing, with a reduction treatment, a surface oxide film in a mixed gas of an inert gas and a reductive gas prior to, or after, said nitrogen absorption treatment.