ArcelorMittal S.A.
Method for improving the formability of steel blanks

Abstract:

A method to improve the formability of steel blanks, for steels containing at least 5% martensite, and possibly some ferrite, bainite and residual austenite and having an ultimate tensile strength of at least 500 MPa and possibly having a metallic coating layer on at least one side, wherein the steel blank is heat-treated on at least part of its peripheral thickness using at least one heat source, which heats the steel in a heat-treated zone to a temperature between 400.degree. C. and 1500.degree. C. without melting the steel in any points of the heat-treated zone.