Study On Chemical Metallurgical Reaction Characteristics Of Interface Between Multicomponent Slag And Refractory

In iron and steel production,Mg O-C refractories have been widely used in the lining of converter and electric furnace.Due to the harsh working environment,the research on the damage mechanism of such refractories has been a hot spot for metallurgical workers.At present,the research mainly focuses on the melting properties and behavior of slag at high temperature,but there is little research on the erosion of slag on refractory and interface reaction.In this paper,the chemical metallurgical reaction characteristics of the interface between slag and refractory were studied,and the erosion mechanism of the reaction process was explored.Through slag performance tester and Factsage theoretical calculation,the basic performance of slag is explored:when the basicity of slag increases from 2.5 to 3.5,Ca O content in slag increases,resulting in more high melting point materials,which makes the melting temperature,viscosity and melting temperature of slag increase in different degrees,at the same time,slag structure tends to be simple,viscous flow activation energy is reduced.With the increase of Mg O content from 8%to 12%,high melting point forsterite and other phases are gradually precipitated from the slag,which makes the melting temperature,viscosity and viscous flow activation energy of slag increase.During the wetting process between slag and Mg O-C refractories,with the increase of furnace temperature,the slag gradually melts and spreads on the refractory surface.Fe O in the slag is reduced by C in Mg O-C refractories to produce CO and CO₂,which makes the slag volume increase continuously.When there is enough gas,the volume of molten slag decreases obviously when the gas escapes.At the same time,due to the generation of gas,the slag is resistant to corrosion and the position of the surface of the pyrotechnic material also deviates until the wetting angle remains unchanged.With the increase of basicity in slag,the viscosity of slag increases,the activity of Fe O decreases,and the diffusion of slag to refractories is restrained,and the final equilibrium contact angle increases;with the increase of Mg O content in slag,the solubility of Mg O decreases,resulting in the increase of contact angle in final equilibrium state;with the increase of surface roughness of refractory,the deviation degree of slag to both sides of refractory material It has little effect on the wetting angle.The results show that when the basicity of slag increases from 2.5 to 3.5,the surface tension of slag increases gradually,the interface energy of final state increases,the depth of slag erosion refractory decreases by 81.06?m,and a large number of low melting point compounds CMS(Ca Mg Si O₄)are generated to accelerate the erosion of refractory,and the high melting point solid solutions of C₂S(Ca2Si O4)and M₂S(Mg2Si O4)are formed to block up.With the increase of Mg O content in the slag,the surface tension of the slag also increases.When the Mg O content is higher than10%,with the increase of Mg O content in the slag,the interface energy increases continuously,the erosion depth of slag to refractory decreases by 32.43?m,the Mg O content increases gradually,and the high melting point M₂S increases continuously,which blocks the refractory.With the increase of the surface roughness of the refractory,the depth of the slag erosion of the refractory is between 30-50?m,and the composition of the slag is the main reason for the damage of the refractory.The change of surface roughness has little effect on the change of interface energy during the reaction between slag and refractory.