مقايسه خواص جرم هاي ريختني آلومينا - اسپينل با آلومينا - منيزيا

Comparision of Alumina-Spines and Alumina-Magnesia Castable Refractory properties

Nowadays, Industrial application of alumina-magnesia and alumina-spinel castable refractories in secondary ladle metallurgy is under expanding. Itʹs mentioned that alumina-magnesia castable has better corrosion resistance and alumina-spinet castable has good thermal shock properties. The goal of this study was the determination of spinet formation control enhancing the thermal shock properties of alumina-magnesia castable refractories.ln this study alumina - magnesia castable whit 5-7% dead-bum magnesia were compared with alumina-spinel castabe with 10-17% spinet from point of view of cold modulus of rupture, thermal shock properties; phase and microstructural analysis. The particle size distribution In both castables were on the base on Anderiasen equation whit q=0.3. The cement content in each castable was 5% wt and the used deflocculant was sodium hexa meta phosphate. The results showed that the deflocculation of alumina- magnesia castable was difficult and the loss of some properties could be related to it. With thermal shock about 1250°C, the loss of strength in alumina magnesia containing samples up to 5 cycles could be seen and that was more than alumina-spine] containing samples. But after 10 thermal shock cycles, the strength variations were the same.