Estimation of Thermal Expansion of Silica Refractory Based on its Mineralogy

Abstract

The paper examines the possibility of estimation of Thermal Expansion (TE) of silica refractory up to 1000°C, based on its mineral contents, particularly SiO2 polymorphs. For that purpose a very accurate quantitative X-ray diffractometric (QXRD) method for estimation of quartz, cristobalite, and tridymite and an optical method for Si glass were standardized in the authors’ laboratory. The total TE caused by these Si polymorphs up to 1000°C was found to be almost equal to that estimated by the conventional dilatometric method showing differences in the third decimal place only. The method is much quicker than the dilatometric method.