Influence of firing temperature on correlation between thermal shock and mechanical impact resistance of refractory castables

Three refractory castables used in the aluminum industry were investigated to establish correlations, which can be applied in practice, among the rele vant properties important for performance in service. To determine the infl uence of firing temperature on the correlations, samples were fired at 1200 and 1450 degreesC followed by mechanical impact (at 900 degreesC) and ther mal shock tests (quenched from 950 degreesC into water). The relevant prope rties were evaluated including modulus of rupture, elastic modulus, work of fracture. and thermal expansion coefficient. The results show that there i s a positive correlation between thermal shock and the mechanical impact re sistance was well as with the sigma R-o(st) parameter at 1200 degreesC. Two other positive correlations were established at 1450 degreesC, the first i nvolving mechanical impact resistance, modulus of rupture, and sigma R-o(st ), and the second between thermal shock resistance and the R"" and R-st par ameters.