Patent · US Active

Steel sheet having high tensile strength and ductility

US10428400B2 · kind B2 · utility

1Cited by

6References

14Claims

0Family size

Assignee

Arcelormittal France · FR

Inventors

Pascal Drillet · Rozérieulles, FR
Damien Ormston · Dunkerque, FR

Key dates

Filing date	Jan 25, 2018
Grant date	Oct 1, 2019
Priority date	—
Expiry date	Apr 9, 2038

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/12799
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

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%.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.