公开(公告)号：US20220056543A1

公开(公告)日：2022-02-24

申请号：US17276435

申请日：2018-09-09

Applicant: ARCELORMITTAL

Inventor： Sujay SARKAR

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/18 ,  C23C2/06

Abstract: A hot rolled steel sheet having a chemical composition including, in weight %: 0.15%≤C≤0.20%, 0.50%≤Mn≤2.00%, 0.25%≤Si≤1.25%, 0.10%≤Al≤1.00%, with 1.00%≤(Al+Si)≤2.00%, 0.001%≤Cr≤0.250%, P≤0.02%, S≤0.005%, N≤0.008%, and optionally one or more elements among: 0.005%≤Mo≤0.250%, 0.005%≤V≤0.250%, 0.0001%≤Ca≤0.003% and 0.001%≤Ti≤0.025%, the remainder being Fe and unavoidable impurities, and wherein the microstructure includes in surface fraction, ferrite and bainite, the sum of which being greater than 5% and strictly lower than 20%, the remainder consisting of tempered martensite.

公开(公告)号：US20210340642A1

公开(公告)日：2021-11-04

申请号：US17279546

申请日：2019-09-02

Applicant: ArcelorMittal

Inventor： Sujay SARKAR ,  Xavier BANO ,  Guillaume MARCIREAU ,  Blandine OEHLER

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/58 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00

Abstract: A hot rolled steel sheet having a composition including the elements, expressed in percentage by weight 0.11%≤Carbon≤0.16%, 1%≤Manganese≤2%, 0.1%≤Silicon≤0.7%, 0 02%≤Aluminum≤0.1%, 0.15%≤Molybdenum≤0.4%, 0.15%≤Vanadium≤0.4%, 0.002%≤Phosphorus≤0.02%, 0%≤Sulfur≤0.005%, 0%≤Nitrogen≤0.01%, and can contain one or more of the following optional elements 0%≤Chromium≤0.5%, 0%≤Niobium≤0.05%, 0.0001%≤Calcium≤0.005%, 0%≤Boron≤0.001%, 0%≤Magnesium≤0.0010%, 0%≤Titanium≤0.01%, with 0.3%≤Mo+V+Nb≤0.6%, the remainder composition being composed of iron and unavoidable impurities, the microstructure of steel sheet including in area fraction, 70% to 90% Bainite, 10% to 25% Ferrite wherein the cumulated amounts of Bainite and Ferrite is at least 90% and a cumulated amount of Residual Austenite and Martensite is between 0% and 10%.