低延性陶瓷材料高温K_R-曲线行为  

The K_R-Curve Behavior of Ceramic Materials at High Temperatures

作　　者：白世鸿[1] 乔生儒[1] 纪岗昌[1] 康沫狂[1] 张行安[2] 

机构地区：[1]西北工业大学材料学院401教研室,西安710072 [2]北京航空材料研究院,北京100095

出　　处：《材料工程》2002年第6期29-31,共3页Journal of Materials Engineering

摘　　要：在高温下采用加载 -卸载技术与柔度标定相结合的方法测量了 Si C陶瓷材料的 KR-曲线行为。结果表明 :在高温下陶瓷材料 KR 随裂纹长度的增加而提高。随温度提高 ,陶瓷材料韧化指数 m减小 ,裂纹阻力降低 ,其 KR曲线越平坦。陶瓷材料在高温下增大的 KR曲线行为 ,与裂纹的转向及裂纹尾区裂纹表面之间的相互作用密切相关。加载 -卸载技术与柔度标定相结合的试验方法 ,对测量陶瓷材料高温 KR-曲线是一种有效简便的方法。The K R curve behavior for SiC material was measured by loading unloading technique combined with compliance calibration at high temperatures in this paper The testing results indicate that the K R increases with increasing crack length at high temperatures; with temperatures increasing, the toughening exponent of ceramic materials decreases and the K R curves become flat The increased K R curve behavior at high temperatures for ceramics is relevant with the crack deflection and the interaction between crack surfaces in wake area behind the crack tip The method of loading unloading combined with compliance calibration is an effective and simple test technique for measuring K R curve behavior of ceramics at high temperatures

关 键 词：陶瓷 KR-曲线 加载-缺载技术 柔度标定 碳化硅 显微结构 塑性变形 

分 类 号：TQ174.1[化学工程—陶瓷工业]