公开(公告)号：US11702717B2

公开(公告)日：2023-07-18

申请号：US16761158

申请日：2017-11-03

Applicant: APERAM

Inventor： Pierre-Olivier Santacreu ,  Coralie Parrens ,  Jean-Benoît Moreau

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C21D1/42 ,  C22C38/54 ,  C22C38/48 ,  C22C38/44 ,  C22C38/42 ,  C22C38/04 ,  C22C38/00

CPC classification number: C21D9/46 ,  C21D1/42 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C22C38/001 ,  C22C38/002 ,  C22C38/04 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/54 ,  C21D2211/004 ,  C21D2211/005 ,  C21D2211/008

Abstract: The disclosed martensitic stainless steel is defined in its composition is by specified ranges of weight percentages of C; Mn; Si; ≤Mn+Si; ≤S; 10,000×Mn×S; P; Cr, with [Cr−10.3−80*(C+N)2]≤(Mn+Ni); Ni; Mo; Mo+2W; Cu; Ti; V; Zr; Al; O; Ta; Nb; (Nb+Ta)/(C+N); Nb; N; Co; Cu+Co; Cu+Co+Ni; B; rare earths+Y; Ca; the remainder being iron and impurities resulting from processing. Its microstructure includes at least 75% martensite, at most 20% ferrite and at most 0.5% carbides, the size of the ferrite grains being between 4 and 80 μm, preferably between 5 and 40 μm. Also disclosed is a method of manufacturing such steel.