Study On High Basicity Refining Slag Desulphurization Effect And Foaming Properties Of LF Furnace

Sulfur is one of the common harmful elements in steel on steel performance will cause many adverse effects. Sulfur as surface active elements, in the form of sulfide segregation in the steel grain boundaries or out of phase interface usually. It can cause great harm to the performance of the steel, will cause the steel brittleness and influence the mechanical properties of steel, weldability, corrosion resistance and so on. Therefore the choice of refining slag of LF refining process is very important.This research to reduce sulfur content in steel for the purpose of, combined with the metallurgical process of steel slag heat of reaction force and dynamic conditions, By using the orthogonal experimental design, designed on the basis of the CaO-SiO2-Al2O3slag series and MgO, CaF2, BaO for adding accessories desulfurization refining slag. Nine different groups of slag samples for melting point and melting speed test experiment, viscosity test experiment and desulfurization experiment. We analysis of the refining slag components on slag viscosity and melting point, melting speed, the desulfurization rate influence and reason, then we optimize the refining slag. The best composition of refining slag follows: basicity (R) is5, the content of BaO is10%, the content of Al2O3is23%, the content of CaF2is10%,the content of MgO is7%.On the basis of orthogonal experiment we have the melting point and melting speed test experiment, desulfurization experiment to the different size of refining slag, detailedly analyzed of the particle size on the causes of refining slag melting temperature, melting speed and the desulfurization rate. It is concluded that reduce the granularity of the refining slag sustably can reduce refining slag melting temperature, increase the melting speed, improve the reaction dynamics condition of steel slag and can significantly improve the desulfurization efficiency of refining slag.At the same time, the research experiment of refining slag foaming, the quantity of foaming agent, refining slag viscosity, foaming agent particle size were considered, the results showed that the amount of foaming agent increases in a certain range is helpful to improve the foaming propertiesthe of refining slag, For the high basicity refining slag, foaming agent addition is10%, grain is too small is not conducive to the refining slag foaming, appropriately increase the granularity of the foaming agent can significantly improve the refining slag foaming.