ArcelorMittal S.A.
A Method for the Manufacturing of Liquid Metal Embrittlement Resistant Zinc Coated Steel Sheet

Abstract:

The present invention relates to a method for the manufacture of a coated steel sheet comprising the following successive steps: A. the coating of the steel sheet with a first coating consisting of nickel and having a thickness between 600 nm and 1400 nm, the steel sheet having the following composition in weight: 0.10<C<0.40%, 1.5<Mn<3.0%, 0.7<Si<3.0%, 0.05<Al<1.0%, 0.75<(Si+Al)<3.0%, and on a purely optional basis, one or more elements such as Nb.ltoreq.0.5%, B.ltoreq.0.010%, Cr.ltoreq.1.0%, Mo.ltoreq.0.50%, Ni.ltoreq.1.0%, Ti.ltoreq.0.5%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, B. the recrystallization annealing at a temperature between 820 to 1200.degree. C., C. the coating with a second coating based on zinc not comprising nickel.