ZrO2增韧Al2O3陶瓷耐磨性的研究

本文对五种不同含量ZrO_2增韧Al_2O_3陶瓷在磨粒磨损条件下的耐磨性进行了试验研究。试验结果表明,ZrO_2增韧Al_2O_3陶瓷的磨损机理不同于金属,它并不是简单的显微切削机理或犁沟机理,其耐磨性与陶瓷的硬度和弹性模量没有单调的依赖关系,而与材料的断裂韧性和抗弯强度呈现比较一致的趋向关系。扫描电镜对摩擦表面和抗弯断口的对比观测表明,ZrO_2增韧Al_2O_3陶瓷磨损破坏机理属于一次性脆性断裂机理。因此,欲提高该陶瓷的耐磨性应当着重于提高陶瓷的韧性和强度。利用ZrO_2的马氏体相变,可望提高陶瓷的韧性和强度,故可望提高Al_2O_3基陶瓷的耐磨性。

STUDY ON ABRASIVE WEAR RESISTANCE OF ZTA CERAMICS

The abrasive wear resistance of ZTA ceramics with five different ZrO_2 contents wasstudied. The results show that abrasive wear meetraniam of ZTA ceramics is different from that of metals, it is not a microcutting or ploughing type of mechanism. The abrasive wear resistance is not dependent on hardness and elastic modulus E, but on the fracture toughness and bending strength of materials. The observation of friction surface and bending Fractured surfaces by means of SEM shows that wear failure mechanism of ZTA ceramics belongs to brittle fracture mechanism. Therefore in order to improve the abrasive wear resistance of ZTA ceramics, fracture toughness and strength of ceramics must be increased. Toughness and strength can be increased by means of Martensite phase transformation in ZrO_2, therefore abrasive wear resistance of ZTA will be possibly improved.