公开(公告)号：US20220282360A1

公开(公告)日：2022-09-08

申请号：US17751615

申请日：2022-05-23

Applicant: ArcelorMittal

Inventor： Frédéric BONNET ,  Manuel BOBADILLA ,  Bertrand BELE ,  Valérie DAESCHLER

IPC: C22C38/14 ,  C21D8/02 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/32

Abstract: A steel sheet has a composition comprising, by weight: 0.010%≤C≤0.080%, 0.06%≤Mn≤3%, Si≤1.5%, 0.005%≤Al≤1.5%, S≤0.030%, P≤0.040%, Ti and B such that: 3.2%≤Ti≤7.5% and (0.45×Ti) −1.35≤B≤(0.45×Ti) −0.43, optionally Ni≤1%, Mo≤1%, Cr≤3%, Nb≤0.1%, V≤0.1%, the remainder being iron and unavoidable impurities resulting from the smelting. The steel sheet has a structure consisting of ferrite, at most 10% of austenite, and precipitates comprising eutectic precipitates of TiB2, the volume fraction of TiB2 precipitates with respect to the whole structure being of at least 9%, the proportion of TiB2 precipitates having a surface area lower than 8 μm2 being of at least 96%.