A thermo-damage-dependent thermal shock resistance model for ultrahigh temperature ceramics for temperature rising thermal shock environment

A thermo-damage-dependent thermal shock resistance (TSR) model, which takes into account the sensitivities of thermo-physical properties to temperature and the evolution of the mechanisms of strength of ultra-high temperature ceramics (UHTCs) at elevated temperature is established. The model incorporates the effects of micro-crack size, density, damage evolution, and temperature on TSR of UHTCs. A detailed study about the effects of damage and its different nucleation laws on thermal shock performance of UHTCs is made by using this model. Results obtained show that through material microstructure design to introduce micro-cracks of a certain density and length into UHTCs while manufacturing and control damage evolution as the nucleation mode, not only the high strength of UHTCs can be kept, but also its TSR can be improved enormously.