中文摘要：

研究了氧化钇稳定氧化锆（Y-TZP）陶瓷在室温至77K间的抗弯强度与断裂韧性变化规律，发现与室温相比，强度和韧性皆有显著提高，且断裂韧性随温度下降的提高速率高于抗弯强度。通过X射线衍射定量相分析及扫描电镜观察，研究了低温下Y-TZP陶瓷断裂过程的相变规律，分析了低温增强应力诱导相变效应对低温下氧化锆陶瓷力学性能的影响，并揭示了一般陶瓷材料低温下可能发生的力学性能变化的规律。

英文摘要：

Changes of flexural strength and fracture toughness of 3Y-TZP were investigated in the temperature range from room temperature to 77 K. It is found that both of the flexural strength and fracture toughness at 77 K are increased remarkably, compared with that at room temperature. The increasing rate of fracture toughness is higher than that of flexural strength as temperature decreasing. The phase transformation rule of 3Y-TZP ceramic during the fracture process at the cryogenic temperature was investigated by XRD and TEM results. The influence of stress induced phase transformation effect by cryogenic temperature enhancement on the mechanical properties of 3Y-TZP ceramic was analyzed. Finally the change rule of possible mechanical properties of the normal ceramic materials at cryogenic temperature was revealed.