Interfacial reaction between different MgO-based refractories and the CaO-FeOx-SiO2 slag system at 1400°C

Interfacial reactions between MgO-Al 2 O 3 , MgO-Cr 2 O 3 , and MgO-C refractories and the CaO-FeO x -SiO 2 slag system were investigated at 1400 °C under Ar atmosphere. Sessile drop tests were carried out to observe the behaviors of the liquid CaO-FeO x -SiO 2 slag with different basicities (CaO/SiO 2 : 0.25, 1.0, and 1.5) on the MgO-Al 2 O 3 , MgO-Cr 2 O 3 , and MgO-C refractories. Furthermore, the corrosion behaviors of MgO-Al 2 O 3 , MgO-Cr 2 O 3 , and MgO-C in contact with the liquid CaO-FeO x -SiO 2 slag (S2, CaO/SiO 2 =1.0) were studied using immersion tests for 30 min. As a result, the MgO-Cr 2 O 3 refractory showed higher resistance against the slags than the MgO-Al 2 O 3 and MgO-C refractories, with less dissolution and no gas reactions. The chemical reaction between MgO-Al 2 O 3 / MgO-Cr 2 O 3 and slag was studied with thermodynamic modeling using the thermochemical software, FactSage 8.3. The calculation results were in good agreement with the results of the sessile drop test and immersion test.