| 摘要 |
<p>PROBLEM TO BE SOLVED: To utilize a raw material for adjusting a slag component at low cost, to produce a high cleanliness steel as the conventional steel by using the raw material having low manufacturing cost. SOLUTION: At the time of deoxidizing molten steel by stirring the molten steel under condition of correcting the surface of the molten steel with slag component adjusting agent, as the component adjusting agent before treating the molten steel, the input quantity of Al from an alloy for component adjusting is added into the molten steel at <=5g/ton of molten steel, and one or more kinds among lime, chamotte, calcium aluminate and ganister and one or more kinds of a m.p. lowering agent of sodium fluoride or fluorspar, are added into the molten steel before treating the molten steel so that the slag component after completing the molten steel treatment becomes 35-60wt.% CaO 30-55wt.% SIO2 , 6-10wt.% Al2 O3 and <=15wt.% the total of the other oxide producing materials and 1.30-1.70 CaO/SiO2 , and thereafter, the molten steel is stirred to deoxidize the molten steel.</p> |
