Investigation of mechanical properties, thermal shock and corrosion behaviours of MgO-MgAl2O4 composite refractories with the incorporation of SnO2

With the incorporation of SnO2 into the MgO-spinel; mechanical properties, thermal shock and corrosion behaviours of composite refractory materials at different compositions have been examined, the variations occurred have been determined, and the parameters affecting those factors have been investigated. The density, strength, Young?s modulus, fracture toughness, fracture surface energy, work of fracture, critical defect size and mean MgO grain size values of the refractories produced at various compositions were measured and evaluated. In addition; the formation of new phase and the microstructural changes formed with the addition of SnO2 into MgO-spinel using XRD measurements and SEM analysis have been determined. The relationships between mechanical properties and structural variations for different compositions have been identified. Thermal stress/shock parameters (R, R''', R'''', Rst) and ?WOF/?S ratios that are used for determining high temperature performance of refractory materials were calculated. Thermal shock behaviour of the samples tested at 500 °C and 1000 °C has been examined and the compositions showing high thermal shock resistance have been determined by evaluating the measured mechanical properties. Furthermore; corrosion resistance has been determined by measuring:i) penetration, ii) depth, iii) width and iv) spreading areas of the corroded regions of refractories tested. The optimum compositions showing a high performance have been identified. The addition of SnO2 into MgO-spinel has improved the mechanical properties, thermal shock and corrosion resistance of refractories markedly.Keywords: MgO, Spinel, SnO2, Composite, Refractory, Mechanical Properties,Thermal Stress/Shock Parameters, Thermal Shock, Corrosion.