Patent ID: 7976647

Claim:
Method for producing a very high mechanical strength steel sheet coated with zinc or zinc alloy, comprising the steps of: producing a slab having a chemical composition, in % by weight, consisting of: 0.060%≦C≦0.250% 0.800%≦Mn≦0.950% Si≦0.300% Cr≦0.015% 0.150%≦Mo≦0.500% 0.020%≦Al≦0.100% P≦0.100% B≦0.010% Ti≦0.050% the balance being iron and impurities resulting from the production of the slab, the microstructure thereof being constituted by ferrite and martensite, hot-rolling then cold-rolling the slab in order to produce a sheet, heating the sheet at a rate of between 2 and 100° C./s until a holding temperature of between 700 and 900° C. is reached, cooling the sheet at a rate of between 2 and 100° C./s until a temperature is reached which is about that of a bath containing molten zinc or a zinc alloy, then coating the sheet with zinc or a zinc alloy by means of immersion in the bath and cooling it to ambient temperature at a cooling rate of between 2 and 100° C./s, wherein the steel is dual-phase; and wherein the steel is used for producing automotive components.