Reaction Mechanism of CA(6), Al(2)O(3) and CA(6)-Al(2)O(3) Refractories with Refining Slag

In this study, to clarify the corrosion mechanism of CA(6) based refractory by refining slag, the static crucible tests for CA(6), CA(6)-Al(2)O(3), and Al(2)O(3) refractory, were carried out and the detail reaction processes were analyzed from the perspective of thermodynamic simulation and structural evolution. From the results, CaAl(4)O(7) plays a vital role in the slag corrosion resistance of the three refractories. Regarding CA(6) refractory, the double pyramid module in CA(6) crystal structure was destroyed very quickly, leading to the rapid collapse of its structure to form the denser CaAl(4)O(7) in high amounts. As a result, a reaction layer mainly composed of CaAl(4)O(7) formed, which effectively inhibited the slag corrosion, so CA(6) refractory exhibits the most excellent slag corrosion. Meanwhile, the formation of CaAl(4)O(7) can also avoid CA(6) particles entering the molten steel to introduce exogenous inclusions. For Al(2)O(3) refractory, the generation of CaAl(4)O(7) is much slower than that of CA(6) and CA(6)-Al(2)O(3) refractory, and the amount generated is also quite small, resulting in its worst slag corrosion among the three crucibles. Therefore, CA(6) based refractory has excellent application potential in ladle refining and clean steel smelting.