氧化铝陶瓷位错形貌的TEM观测

TEM Observation on the Dislocation Morphlogy of Al_2O_3 Ceramic

利用TEM对经过短时间高温1 800℃、高压100 MPa处理后的氧化铝陶瓷位错形貌进行了观察分析。观察到了丰富的位错组态,包括位错阵列线、位错网和位错缠结。采用衍射对比技术,得出位错阵列的柏氏矢量b=1/3<1100>,滑移体系为棱柱滑移,{1120}<1100>。对位错网络形成进行了分析,位错网络为基面滑移1/3<1120>。通过分析,得出该过程中氧化铝基面和棱柱滑移在塑性变形过程中起主要作用。

Extensive dislocation structure was observed by transmission electron microscopy （TEM） in polycrystalline alumina ceramic sintered under a short-time high temperature 1 800℃ and pressure 100 MPa. There existed lots of dislocation structures; dislocation coalescence, dislocation arrays and dislocation network. The burgers vector of the dislocation array was determined by diffraction contrast as 1/3〈 1100〉. The dislocation network formation was discussed, and it belonged to basal sllp system 1/3〈1120〉. Plastic deformation oceured mainly by basal plane slip and prime plane slip.