Manufacturing method for very high-strength, cold-rolled, dual-phase steel sheets

US10190187B2 · kind B2 · utility

Assignee

• ArcelorMittal · LI

Inventors

• Antoine Moulin · Aurec-sur-Loire, FR
• Veronique Sardoy · Metz, FR
• Catherine Vinci · Jury, FR
• Gloria Restrepo Gacess · Salon-de-Provence, FR
• Tom Watershoot · Lokeren, BE
• Mohamed Goune · Pont-à-Mousson, FR

Key dates

• Filing date: Apr 12, 2016
• Grant date: Jan 29, 2019
• Expiry date: Jun 10, 2036

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C2/36
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The present invention provides a cold-rolled and annealed Dual-Phase steel sheet having strength from 980 to 1100 MPa and a breaking elongation greater than 9%. The composition includes the contents being expressed by weight: 0.055%≤C≤0.095%, 2%≤Mn≤2.6%, 0.005%≤Si≤0.35%, S≤0.005%, P≤0.050%, 0.1≤Al≤0.3%, 0.05%≤Mo≤0.25%, 0.2%≤Cr≤0.5%, Cr+2Mo≤0.6%, Ni≤0.1%, 0.010≤Nb≤0.040%, 0.010≤Ti≤0.050%, 0.0005≤B≤0.0025%, and 0.002%≤N≤0.007%. The remainder of the composition includes iron and inevitable impurities resulting from the smelting. A manufacturing method is also provided.