公开(公告)号：EP3392355A1

公开(公告)日：2018-10-24

申请号：EP16875188.1

申请日：2016-09-20

申请人： Daido Steel Co.,Ltd.

发明人： FURUSHO Chihiro ,  TAKABAYASHI Hiroyuki

IPC分类号： C21D8/00 ,  C22C38/00 ,  C22C38/60

CPC分类号： C21D8/00 ,  C22C38/00 ,  C22C38/60

摘要： The present invention is characterized by obtaining a steel having a ferrite cross-sectional area ratio of 95% or more through hot-forging, in a ferrite single-phase region, a steel having a composition makeup containing, in mass%, 0.015% or less of C, 0.02-0.60% of Si, 0.2-2.0% of Mn, 0.050% or less of P, 1.5% or less of Cu, 1.5% or less of Ni, 10.0-25.0% of Cr, 2.0% or less of Mo, 0.30-2.50% of Al, 0.0030-0.0400% of O, 0.035% or less of N, and 0.10-0.45% of S, and in addition, two or more selected from 0.03-0.40% of Pb, 0.03-0.40% of Bi, and 0.01-0.10% of Te, the balance being Fe and incidental impurities, where the masses by percent of the respective elements of C, N, Si, Cr, Mo, and Al, satisfy a predetermined relationship.