US Patent 7699947 Ultrahigh strength hot-rolled steel and method of producing bands

The invention relates to ultrahigh strength hot-rolled steel having a chemical composition consisting of, by weight:0.05%≦C≦0.1%0.7%≦Mn≦1.1%0.5%≦Cr≦1.0%0.05%≦Si≦0.3%0.05%≦Ti≦0.1%Al≦0.07%S≦0.03%P≦0.05%the remainder comprising iron and impurities resulting from the production thereof. Moreover, the inventive steel has a bainitic-martensitic structure which can contain up to 5% ferrite. The invention also relates to a method of producing bands of said steel.