Study On Corundum-mullite Based Gas Curtain Barricade For Tundish

It is a obviously effective way to remove non-metal inclusion and microinclusion to improve the quality of molten steel by gas curtain barricade brick through which blowing inactive gas Ar into tundish. According the tundish working condition, the paper studies the corundum and mullite as main elements based on analysis of foreign gas curtain barricade brick, and it studies importantly the density and permeability castable on some factors which effect the quality of permeability castable of gas curtain barricade such as the partical size distribution , mixing amount of fines, additive and Al₂O₃—SiO₂ Sol-Gel and so on.And, we finish the pilot production of gas curtain barricade by mathematical model and optimum recipe.The results indicate that the gas curtain barricade which is composd of corundum and mullite materials is a better choice , it has high mechanical robustness, better volum stability and permeability, well pore distribution, and it could produce uniform aperture and more than 30% of apparent porosity depended on itself accumulation of article. Adding Al₂O+3—SiO₂ Sol-Gel system into fines has obvious results for improving strength of porous castable.The mechanics is different for different adding forms.The forms of addition Al₂O₃—SiO₂ Sol-Gel and immersion Al₂O₃—SiO₂ Sol-Gel which improve strength are because of thick and thin colloid substance that joint particle and particle.But form of adding dried Gel powder improving strength is due to mullite whisker at 1200℃,at the same time, it betterments the permeability of castable.