摘要
首先从理论上推导了展状介质超声脉冲回波的解析表达式，对各界面信号进行了分析。指出多层介质超声回波是各界面信号的叠加。应用自适应噪声抵消去除超声回波中的零界面和一界面信号，可以将二界面信号提取出来。对模拟和实测层状介质超声回波信号处理表明，方法是可行的。根据得到的二界面信号的幅度和起始时间，可以对二界面的深度和粘结情况进行评价。
The analytic expression of received echo in multilayer NDT is derived first. From the analytic resolution,interface signals are analyzed. It is concluded that the received ultrasonic echo of multilayer is composed of all theinterface signals. Therefore, the second interface signal can be extracted by the adaptive canceling of the zero and flrstinterface signals. The processing effect to the ultrasonic echoes of simulation and real multilayer is pretty well. From theamplitude and arrival time of the second interface signals, the bond and the depth of the interface can be evaluated.
出处
《声学学报》
EI
CSCD
北大核心
2000年第4期351-356,共6页
Acta Acustica
基金
国家自然科学基金
中国科学院声学研究所所长基金
