论文部分内容阅读
The thermal shock fatigue behaviors of pure hot-pressed alumina and 30 wt.% TiC/Al_2O_3 composites were studied.The effect of TiC and Al_2O_3 starting particle size on the mechanical properties of the composites was discussed.Indentation-quench test was conducted to evaluate the effect of thermal fatigue temperature difference(ΔT)and number of thermal cycles(N)on fatigue crack growth(Δa).The mechanical properties and thermal fatigue resistance of TiC/Al_2O_3 composites are remarkably improved by the addition of TiC.The thermal shock fa- tigue of monolithic alumina and TiC/Al_2O_3 composites is due to a“true”cycling effect(thermal fatigue).Crack deflection and bridging are the predominant reasons for the improvement of thermal shock fatigue resistance of the composites.
The thermal shock fatigue behaviors of pure hot-pressed alumina and 30 wt.% TiC / Al_2O_3 composites were studied. The effect of TiC and Al_2O_3 starting particle size on the mechanical properties of the composites was discussed. Indentation-quench test was conducted to evaluate the effect of thermal fatigue temperature difference (ΔT) and number of thermal cycles (N) on fatigue crack growth (Δa). The mechanical properties and thermal fatigue resistance of TiC / Al_2O_3 composites are remarkably improved by the addition of TiC. The thermal shock Cycling of the monolithic alumina and TiC / Al_2O_3 composites is due to a “true” cycling effect (thermal fatigue). Crack deflection and bridging are the predominant reasons for the improvement of thermal shock fatigue resistance of the composites.