AUSTENITIC STAINLESS STEEL SHEET AND PROCESS FOR PRODUCING HIGH ELASTIC LIMIT NONMAGNETIC STEEL MATERIAL THEREFROM

摘要

1/2Provided is a raw steel sheet for obtaining a high strength nonmagnetic austenitic stainless steel material therefrom which has a high elastic limit stress and excellent toughness. The raw steel sheet is an austenitic stainless steel sheet that has a comp osition which contains in terms of mass% up to 0.12% C 0.30 3.00% Si 2.0 9.0% Mn 7.0 15.0% Ni 11.0 20.0% Cr and up to 0.30% N and further contains at least one of up to 3.0% Mo up to 1.0% V up to 1.0% Nb up to 1.0% Ti and up to 0.010% B with the remainder comprising Fe and unavoidable impurities and which has an Ni equivalent of 19.0 or greater wherein when the average crystal grain diameter of the austenite is expressed by d (�m) the value of d is 0.40 or greater. The raw steel sheet has the property of having a magnetic permeability � of 1.0100 or less after cold worked so as to result in an equivalent strain of 0.50 or greater.