公开(公告)号：US11279984B2

公开(公告)日：2022-03-22

申请号：US16470728

申请日：2017-12-19

Applicant: ArcelorMittal

Inventor： Jean-Marc Pipard ,  Marc Olivier Thenot ,  Pierre Targy

IPC: C21D8/02 ,  C22C38/00 ,  C22C38/06 ,  C22C38/34 ,  C22C38/38 ,  C21D1/19 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28

Abstract: A cold rolled steel sheet, the steel containing, in weight percentage, 0.19%≤carbon≤0.24%, 1.9%≤manganese≤2.2%, 1.4%≤silicon≤1.6%, 0.01%≤aluminum≤0.06%, 0.2%≤chromium≤0.5%, phosphorus≤0.02%, sulfur≤0.003%, the balance including iron and unavoidable impurities, the steel sheet having a microstructure containing 5% to 15% of tempered martensite, 10% to 15% of residual austenite, the balance containing bainite, bainite content being at least 70%, is described. Also described is a manufacturing method and with use of such grade for making vehicle parts.