Patent ID: 8882880

Claim:
A method for producing Al—Si-killed steel having a chemical composition by weight percentage of C≦0.005%, Si: 0.1-2.4%, Mn: 0.1-0.5%, P≦0.2%,S≦0.002%, Al: 0-1.2%, N≦0.005%, Ti≦0.0015% and a balance substantially being Fe and inevitable impurities; the method comprising obtaining the steel having the said chemical composition by hot metal preprocessing and smelting with the steps of, forming a top ladle slag containing sulfur during smelting, performing decarburization of the steel, modifying the top ladle slag by adding a calcium-aluminum based modifier of 0.6-1.7 kg/t steel to control a content of total iron (T.Fe) in the top ladle slag composition at ≧5% by weight percentage and a content of Al 2 O 3 at ≦23% by weight percentage after decarburization, employing ferrosilicon, ferroaluminum and ferromanganese to perform deoxidation and alloying, performing deep desulfurization using a desulfurizer having a desulfurizing efficiency of 50% to 70%, and ingoting the steel.