The Effects of Constraint, Size and Aspect Ratio on Thermal Shock Resistance of ZNS Wave-Transparent Ceramic in its Actual Service

The thermal shock resistance (TSR) of ZnS wave-transparent ceramic depends on not only the mechanical and thermal properties of materials, but also the aerodynamic heating, pneumatic pressure, external constraint, size, aspect ratio and other factors in its actual service process. The theoretical model was established by introducing the analytical solution of transient heat conduction problem of ZnS plate under aerodynamic heating into its thermal stress field model and the pneumatic pressure was introduced. The present work mainly focused on the influences of constraint, size and aspect ratio on the critical rupture temperature difference of ZnS plate subjected to aerodynamic heating and pneumatic pressure. The numerical simulation was also conducted to verify the theoretical model. The results show that the large heat transfer condition corresponds to the poor TSR unless the constraint is too strong; the square plate provides the better TSR in case of different pneumatic pressures; a reasonable side length according to the range of pneumatic pressure would lead to the better TSR.