The basic function of refining slag is to desulphurize and deoxidize molten steel, absorb impurities in molten steel, so as to purify liquid steel, bubble and submerged arc to prevent molten steel from absorbing gas and keeping warm. Refining slag can be divided into basic slag, flux and foaming agent by its functions. Through the comprehensive action of each part, the refining slag has the functions of low melting point, proper viscosity, good foaming property, deoxidizing desulfurization and impurity absorption, which ensures good metallurgical effect. The following is a brief analysis of its performance and influencing factors:

1. Melting point. The melting point of refining slag is generally controlled in the range of 1300-1500 ℃.

2. Viscosity. The viscosity of slag is directly related to its melting point temperature.

3. Foaming property. The foaming property of refining slag is related to viscosity, surface tension and density of slag, which is generally measured by foaming index.

4. Desulfurization, deoxidization and adsorption of impurities. The process of deoxidization, desulfurization and impurity adsorption of refining slag is a diffusion chemical and physical process occurring at the interface of steel slag. Good white slag and proper amount of slag are important conditions for deoxidizing desulfurization and adsorbing impurities.

The viscosity of refining slag has great influence on steel refining. Viscosity is an important performance index of refining slag to be controlled. The viscosity of refining slag has an important influence on whether the smelting process can be carried out smoothly, and also has an important impact on heat and mass transfer, deoxidization and desulfurization reaction rate, steel loss in slag and lining life. The viscosity of solute mainly depends on the composition and temperature of slag. Generally, the viscosity of LF refining slag is 0.25-0.5pa. S.

In addition, the viscosity of refining slag will change with the change of temperature, and the dosage of slag transfer slag is 41%. In addition, the content of various metals in different refining slag systems is different, especially the content of alumina has a great influence on the viscosity of refining slag. Alumina is an amphoteric oxide. In alkaline slag, when the content of alumina is less than 10%, the viscosity of refining slag system increases with the increase of alumina content when the content of alumina is more than 10%.

In the practical application of refining slag, it is necessary to strictly control the composition ratio of refining slag, select the products suitable for production and use, ensure that its viscosity can meet the production requirements, so as to produce better steel