POSCO Holdings Inc.
HIGH-STRENGTH NONMAGNETIC AUSTENITIC STAINLESS STEEL AND MANUFACTURING METHOD THEREFOR

Abstract:

Disclosed are austenitic stainless steel that can exhibit high strength while having non-magnetic properties, and a manufacturing method thereof. The high strength non-magnetic austenitic stainless steel according to an embodiment of present disclosure includes, in percent (%) by weight of the entire composition, C: 0.02 to 0.12%, Si: 1.2% or less, Mn: 0.5 to 2.0%, Cr: 17.0 to 22.0%, Ni: 11.0 to 15.0%, Mo: 3.0% or less, N: 0.25% or less, the remainder of iron (Fe) and other inevitable impurities, satisfies C+N: 0.25% or more, and satisfies following Formulas (1) and (2). [{Cr+Mo+1.5*Si+18}/{Ni+30*(C+N)+0.5*Mn+36}+0.262]*161-161-log(cooling rate)<0 (1) 551-462*(C+N)-9.2*Si-8.1*Mn-13.7*Cr-29*Ni-18.5*Mo.ltoreq.-200 (2)