Abstract
Crack initiation and propagation behavior in alumina pellets subjected to thermal shock with various temperature differences (ΔT) were investigated. Change in specimen surface area, i.e., in crack surface area, resulting from the thermal shock was measured non-destructively by a BET surface area measurement technique. The extent of crack propagation at a certain ΔT was compared on the specimens subjected to only a single thermal shock and specimens repeated thermal shock with a gradual increase in the temperature difference up to the ΔT. The single thermal-shocked specimens sustained severer damage than the repeatedly thermal-shocked specimens. Good coincidence was obtained between calculated and measured crack surface areas, demonstrating the validity of the BET technique as a non-destructive method for evaluating the thermal shock damage.
