Mechanism analysis of thermal shock properties for ZrB2-20%SiCp-10%AlN ultra-high temperature ceramic with the surface defects

Abstract An indentation–quenching test was used to characterize thermal shock properties of ZrB 2 -20%SiCp-10%AlN ceramic with surface defects that arisen from Vickers indentation. It showed that the thermal shock resistance was affected by the length of pre-crack and the thickness of specimen. The critical temperature difference was up to 550 °C and the residual strength approached to a constant in this paper. Thermal stress intensity factor ( K I ) was investigated at temperature of 550 °C by the semi-elliptical surface crack physical model, and it indicated that K I ascended firstly and descended afterwards. The crack propagation behavior was characterized by calculating the difference between the crack resistance and K I . The main influencing factors for K I were also discussed and analyzed here.