| 摘要 |
<p>PURPOSE:To produce a steel material of wire rod for manufacturing steel wool, etc., with converter-continuous casting method by reacting molten steel after tapping from the converter with slag specifying content of Al2O3, etc., and specifying sol. oxygen concn. CONSTITUTION:The molten steel in a ladle after tapping from the converter, is covered by adding the slag having 2-15% Al2O3, 0.60-1.5 CaO/SiO2 and <=20% the balance component at >=1kg/t of molten steel and stirred. Then, the slag and the molten steel are reacted. And after making <0.005% [O] in the molten steel, the continuous casting is executed. In the case Al2O3 concn. is higher, [O] is lowered, but hard inclusion A having high Al2O3 content is increased and on the other hand, in the case this is lower, hard inclusion S having high SiO2 content is increased and the service life of a tool is shortened. In the case CaO/SiO2 is high [O] is lowered, but fluidity of the slag is becomes bad and reaction with the molten steel is delayed and in the case O is too low, with inclusion A is increased. On the other hand, in the case the above ratio is low, the inclusion S is increased and [O] is made to too high and defect in a cast slab after casting is developed.</p> |
