Thermodynamic corrosion behavior of AL(2)O(3), ZrO2 and MgO refractories in contact with high basicity refining slag

摘要

Al2O3, MgO, and ZrO2 containing refractories are widely used in the steel industry. The corrosion behavior of high basicity refining slag on three kinds of refractory materials was studied. Regarding the Al2O3 refractory, Al(2)o(3) crucible would partially dissolve into the slag, and form a transition layer composed of CaAl12O19 and CaAl4O7 at the same time. For ZrO2 refractories, the refining slag and the ZrO2 crucible produce a transition layer composed of calcium zirconate with the high melting point of CaZrO3, CaZr4O9 and Ca6Zr19O44, which prevents the contact between the ZrO2 crucible and the refining slag to inhibit the further corrosion of the crucible. There is no chemical reaction between the MgO crucible and the refining slag. However, the pores in the MgO crucible matrix are filled with liquid slag. The corrosion mechanisms were studied by experiments combined with thermodynamic calculations, and the relative corrosion model has been established.