基于激光测振仪的薄钢板损伤无损检测方法

摘要

This paper studies nondestructive testing method of locating defect in thin plate-like structure based upon the active lamb wave detecting technique with the aid of laser vibrometer.In the experiment,lamb wave is actuated by single piezoelectric transducer (PZT)and received by laser vibrometer.Firstly,the propagation property of lamb wave in thin steel plate was explored, the relevant dispersion curves were drawn, and finally the experimental actuation parameters were optimized.By integration of elliptic imaging theory and probability imaging algorithm,it is effective to get two-dimensional images of defect in plate-like structure from signals received by omnidirectional multi-sensor array.The result shows that this kind of nondestructive method can locate man-made damage and get two-dimensional images of defect in an effective way.%基于非接触式激光测振仪的主动兰姆波检测技术，分析了薄钢板损伤的无损检测方法。试验采用单压电片激励，激光测振仪周向阵列接收的检测方式。根据兰姆波在钢板中的传播特性，绘制出相应的频散曲线，确定试验最佳激励参数，进而结合椭圆定位原理和概率成像算法，对激光测振传感器周向阵列采集到的多组信号进行损伤成像。结果表明，该无损检测方法可以有效地检测出损伤，实现损伤的二维成像定位。