【摘要】 以Ce -ZrO2 为基体 ,通过复合不同加入量的第二相CePO4 颗粒 ,并借助扫描电子显微镜对材料压痕、磨削及切削表面进行分析 ,研究了CePO4 /Ce-ZrO2 陶瓷材料的可加工机理。单相CePO4 材料的弯曲断口显示出层片状断裂机制 ;而复相CePO4 /Ce -ZrO2 陶瓷由于两相之间弱结合界面的存在 ,压痕裂纹扩展形式发生明显变化 ,由连续扩展机制过渡为不连续扩展。基于上述两种重要机制形成的大量微裂纹是赋予材料可加工性的主要原因 ,材料加工去除是以微裂纹的连接来实现的。同时 ,大量微裂纹起到耗散主裂纹扩展能量的作用 ,有效阻止了较大裂纹的形成 ,使材料加工损伤大大降低。最后 ,给出了CePO4 /Ce -ZrO2 陶瓷加工机理的简单模型更多还原

【Abstract】 Mechanism of machining for two phase composites CePO 4/Ce-ZrO 2 fabricated by adding different amount of CePO 4 into Ce-ZrO 2 was investigated. The surfaces after indenting, grinding and cutting were analyzed with the aids of SEM. It is found that multi layered fracture occurred within single phase of CePO 4 in cross_section micrograph. After adding CePO 4 in Ce-ZrO 2, the propagation mechanism of indentation cracks changed obviously, from the continuous form to the discontinuous one due to the existence of weak interfaces between CePO 4 and Ce-ZrO 2. Based on the above two important mechanisms ,the material is endowed with machinability by the formation and linkage of microcracks. At the same time, microcracks dissipate the propagation energy of the main crack, which effectively prevents the formation of macrocrack after machining. It decreases the machining damages a lot. Finally, a simple model of machining mechanism of CePO 4/Ce-ZrO 2 is brought forward.更多还原