| 摘要 |
The invention relates to a high resistance steel band or sheet having a substantially ferritic or martensitic structure, with a martensitic part comprised between 4 and 20 %. In addition to the iron and the impurities resulting from the steel-making process, said steel band or sheet contains (in mass %) 0.05 - 0.2 % C, </= 1,0 % Si, 0,8 - 2,0 % Mn, </= 0,1 % P, </= 0,015 % S, 0,02 - 0,4 % Al, </= 0,005 % N, 0,25 - 1,0 % Cr, 0,002 - 0,01 % B. Preferably, the martensitic part is comprised between 5 % and 20 % of the substantially ferritic and martensitic structure. The inventive high resistance steel band or sheet which is made of a dual-phase steel exhibits good mechanical and technological properties, even after an annealing process including an over-aging treatment. The invention also relates to a method for producing said steel band or sheet. |
