The method for making steel in a ladle refining furnace process includes the following steps:
1. Transfer the initial molten steel of the converter to the ladle refining furnace, start the electric heating at the refining station and add the slag for a period of time, about 3 to 5 minutes, according to the steel type, the converter endpoint [C] and the slag. The situation of the amount, add the ratio of 0.25～0.5kg according to every ton of molten steel, and add the multi-effect refining agent at one time; Synthetic slag is the material of the prior art and adds according to the existing technological requirements;
Described multi-effect refining agent, is prepared from the component that contains the following percentage by weight: CaC2-45～70%, SiC-5～20%, Al-5～15%, and slow release agent 10～20%; The components of the multi-effect refining agent are equipped with strong deoxidizing elements (Ca, Al, Si), strong foaming elements (C) and slow-release agents that inhibit gas escape.
2. In the ladle refining furnace process, adjust the slag according to the change of the slag; if the thickness of the slag foam cannot be completely submerged or the deoxidation is poor, then add a multi-effect refining agent to adjust the slag, and add 0.05 to 0.05 to 0.05 per ton of molten steel each time. The proportion of 20kg was added to adjust the slag.
3. 5~10 minutes before the end of the ladle refining furnace refining process, add 4~Mkg/furnace of bauxite or ferrosilicon powder or silicon calcium powder to break the slag, eliminate the CaC2 particles in the slag, increase the surface tension of the slag Promote the separation of steel and slag.
In the ladle refining process, if the slag appears from white to gray-black carbide slag phenomenon, then add 5~15kg/furnace bauxite or ferrosilicon powder or silicon calcium powder to adjust the slag, and strengthen the ladle bottom blowing Ar stirring, In order to maintain the foaming of the slag completely submerged arc and the stability of the white slag.
The chemical composition of the multi-effect refining agent is Ca-28~55%, A1-5~15%, C-15~30%, Si-3~15%, and slow release agent 10~20%.
Sustained release agents are oxides that significantly increase slag viscosity and surface tension and inhibit gas escape. Such as active BaO, CaO, MgO, etc.