POSCO Holdings Inc.
HOT ROLLED AND UNANNEALED FERRITIC STAINLESS STEEL SHEET HAVING EXCELLENT IMPACT TOUGHNESS, AND MANUFACTURING METHOD THEREFOR

Abstract:

A non-annealed hot-rolled ferritic stainless steel sheet with excellent impact toughness includes, in percent (%) by weight of the entire composition, C: more than 0 and 0.03% or less, Si: 0.1 to 0.5%, Mn: 1.5% or less, P: 0.04% or less, Cr: 10.5 to 14%, Ni: more than 0 and 1.5% or less, Ti: 0.01 to 0.5%, Cu: more than 0 and 1.0% or less, N: more than 0 and 0.015% or less, Al: 0.1% or less, the remainder of iron (Fe) and other inevitable impurities, and satisfies the following equation (1), and the average grain size of the cross-sectional microstructure in the direction perpendicular to the rolling direction is 60 .mu.m or less. (1500.ltoreq.(1001.5*C+950.6*Mn+1350.5*Ni+395.6*Cu-0.7*Si-1.0*Ti-0.1*Cr-- 1.0*P-1.0*Al+1020.5*N).ltoreq.2200). (1)