陶瓷材料的抗热震参数

Thermal shock resistance parameters of ceramic materials

通过求解无限大平板第三类边界条件的瞬态温度场及瞬态热应力场,分别建立了表面冷却条件下引起平板表面临界应力的临界温差ΔTc的表达式和表面加热条件下引起平板中心面临界应力的临界温差ΔTc′的表达式.计算结果表明,无限大陶瓷平板的ΔTc远远小于相同Biot模数条件下的ΔTc′,而且表面冷却条件下表面达到临界热应力的量纲一时间也小于表面加热条件下中心面达到临界热应力的量纲一时间.

By means of the calculations of transient temperature fields and transient thermal stresses for infinite plate under the convective boundary condition, the formula of critical temperature difference ΔTc leading to the critical stress at the surface in the case of surface cooling and the formula of critical temperature difference ΔTc′ leading to the critical stress at the center in the case of surface heating for infinite ceramic plate are obtained respectively. The calculation results reveal that ΔTc is much lower than ΔTc′ for infinite ceramic plate under the same Biot number, furthermore the dimensionless time for the surface to attain the critical thermal stress in the case of surface cooling is shorter than that for the center to attain the critical thermal stress in the case of surface heating also.