【摘要】 在Al2 O3 /(W ,Ti)C陶瓷复合材料中适量添加稀土元素钇能显著提高其断裂韧性。本文运用SEM与TEM技术 ,从微观结构的角度探讨了其增韧机制。表明 ,由于稀土钇的添加 ,使材料内部形成不同程度的强弱界面 ,它们与扩展中的裂纹相互作用 ,使得裂纹桥联、裂纹分支、裂纹偏转以及微裂纹等增韧机制得到明显增加和加强 ,从而以多种增韧机制及其协同作用共同提高稀土补强Al2 O3 /(W ,Ti)C陶瓷复合材料的断裂韧性。更多还原

【Abstract】 The fracture toughness of the Al\-2O\-3(W,Ti)C ceramic composite material can be increased with the addition of rare earth yttrium,Both SEM and TEM being used for the observation and analysis of the crack propagation patterns,the toughening mechanisms are discussed in detail microstructurally. Results show that both strong and weak interfaces,formed as a result of the addition of yttrium,interact with the propagating cracks,which lead to the increase of the fracture toughness of the Al\-2O\-3/(W,Ti)C ceramic composite through several toughening mechanisms such as multigrain bridging,crack deflection,crack branching and microcracking,etc.and their synergism toughening mechanisms.更多还原