对陶瓷材料在两种压缩加载下破坏过程中的声发射特性进行实验研究。三点弯曲和巴西劈裂实验中,采用多通道声发射系统监测了陶瓷试件的破坏过程。对声发射信号进行分析,结果表明,声发射能量数、事件数、振铃数等参数都反映了材料内部损伤演化扩展直至试件宏观断裂的过程。利用声发射参数可以定位陶瓷试件的破坏位置;试件断面的宏细观分析表明,陶瓷的脆性破坏机制主要是颗粒附近的微裂纹开裂。
Acoustic emission(AE) characteristic of alumina under compressive loading was investigated by experimental method.During three-point-bending test and Brazilian test,advanced multi-channel acoustic emission system was used to detect the failure of alumina.Analyzing the results of acoustic emission,AE energy,AE counts and AE hits changing with loading time reflect the process which is from the growth and evolution of micro-crack to macro-fracture of material.AE parameters are used to determine the location of fracture surface.By micro-macro characteristics,micro-cracks around particles are dominated the brittle fracture of alumina.