Influence of thermal shock damage on the flexure strength of alumina ceramic at different temperatures

Abstract

Alumina ceramic specimens that suffered a specific water quench thermal shock were used for three-point bending test at different temperatures to investigate the effect of thermal shock damage on flexure strength for the first time. Results indicate that the sensitivity of the alumina flexure strength to thermal shock damage decreased with increasing temperature. When evaluating the thermal shock resistance of alumina by using critical thermal shock temperature difference, which determined by thermal shock residual strength at room temperature, will result in one-sided conclusion for the thermal shock resistance of ceramics. The mechanism of sensitivity of alumina ceramic strength to the thermal shock damage at elevated temperature was analyzed by the microstructure of the facture surface with SEM images. Therefore, this study can provide references for engineering application of alumina materials and improve the understanding of thermal shock resistance for ceramic materials.