SiC晶须增韧Al_2O_3－（Ti，W）C陶瓷材料增韧机理的研究

Study of the Toughening Mechanism of SiC Whisker Toughened Al_2O_3-(Ti,W )C Ceramic Material

改善陶瓷材料的脆性是陶瓷研究领域里急待解决的关键性课题。本文在Ａｌ２Ｏ３－（Ｔｉ，Ｗ）Ｃ复相陶瓷中加入不同含量的ＳｉＣ晶须以提高基体材料的断裂韧性。研究表明，ＳｉＣ晶须增韧Ａｌ２Ｏ３－（Ｔｉ，Ｗ）Ｃ复相陶瓷的断裂韧性与烧结密度、晶须含量等因素有关，增韧效果与晶须和基体的复合密切相关，增韧机制主要是裂纹偏转和裂纹桥接机制，同时，Ａｌ２Ｏ３与（Ｔｉ，Ｗ）Ｃ形成的双骨架结构亦使断裂韧性得到提高。

It is the important task to improve the toughness of the ceramic material. During the experiment, the different content SiC whiskers were added into the A12O3-(Ti,W)C matrix to improve the fracture toughness. The results have showed that the fracture toughness is related to the sintering density and whisker content, etc. The toughening effects have a great bearing on the fabrication between whisker and matrix.The toughening mechanisms are crack deflection and bridging. Moreover, the twin-skeleton structure formed by Al2O3 and (Ti,W)C can also improve the fracture toughness.