公开(公告)号：US10214792B2

公开(公告)日：2019-02-26

申请号：US14575475

申请日：2014-12-18

Applicant: ARCELORMITTAL FRANCE

Inventor： Pascal Drillet ,  Damien Ormston

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/38 ,  C21D6/00 ,  C22C38/26 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12

Abstract: The invention relates to a hot-rolled steel sheet having a tensile strength greater than 800 MPa and an elongation at break greater than 10%, the composition of which comprises, the contents being expressed by weight: 0.050%≤C≤0.090%, 1%≤Mn≤2%, 0.015%≤Al≤0.050%, 0.1%≤Si≤0.3%, 0.10%≤Mo≤0.40%, S≤0.010%, P≤0.025%, 0.003%≤N≤0.009%, 0.12%≤V≤0.22%, Ti≤0.005%, Nb≤0.020% and, optionally, Cr≤0.45%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting, the microstructure of the sheet or the part comprising, as a surface fraction, at least 80% upper bainite, the possible complement consisting of lower bainite, martensite and residual austenite, the sum of the martensite and residual austenite contents being less than 5%.

公开(公告)号：US10428400B2

公开(公告)日：2019-10-01

申请号：US15879944

申请日：2018-01-25

Applicant: ArcelorMittal France

Inventor： Pascal Drillet ,  Damien Ormston

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/38 ,  C21D6/00 ,  C22C38/26 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12

Abstract: A hot-rolled steel sheet having a tensile strength greater than 800 MPa and an elongation at break greater than 10% is provided. A composition of the steel includes, the contents being expressed by weight: 0.050%≤C≤0.090%, 1%≤Mn≤2%, 0.015%≤Al≤0.050%, 0.1%≤Si≤0.3%, 0.10%≤Mo≤0.40%, S≤0.010%, P≤0.025%, 0.003%≤N≤0.009%, 0.12%≤V≤0.22%, Ti≤0.005%, Nb≤0.020% and optionally, Cr≤0.45%. A balance of the composition includes iron and inevitable impurities resulting from the smelting. A microstructure of the sheet or part includes, as a surface fraction, at least 80% upper bainite, and a remainder includes lower bainite, martensite and residual austenite. A sum of the martensite and residual austenite, as a surface fraction, is less than 5%.