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针对当前空耦Lamb波缺陷检测的不足, 通过有限元仿真与实验验证的方法, 对多种复合板缺陷类型的空耦Lamb波扫描成像进行了研究.首先, 利用ABAQUS建立了Lamb波在复合板内的三维传播模型, 基于该模型研究了空耦Lamb波在不同类型复合板缺陷扫描检测下的衰减特性, 仿真结果表明, 根据Lamb波扫描信号可以识别出缺陷在扫描方向上的位置与尺寸;然后, 基于仿真结果制定了空耦Lamb波扫描实验方案, 搭建了扫描实验系统, 从两个相互正交的方向对复合板进行扫描检测, 通过比较仿真和实验结果, 验证了有限元模型的正确性;最后, 根据概率损伤算法得到了扫描区域内的缺陷图像, 成像结果表明, 基于扫描检测的空耦Lamb波缺陷成像方法可以有效识别出多种复合板缺陷的尺寸、形状和损伤程度.“,”Aiming at the shortcomings of the current air-coupled Lamb wave defect detection, the finite element simulation and experimental verification methods are used to study the air-coupled Lamb wave scanning imaging of various types of composite plate defects. Firstly, the three-dimensional propagation model of Lamb wave in composite plate is established by using ABAQUS. Based on the model, the attenuation characteristics of the air-coupled Lamb wave in scanning detection under different types of composite plate defect are studied. The simulation results show that the Lamb wave scanning signal can be used to identify the position and size of the defect in the scanning direction. Then, based on the simulation results, an air-coupled Lamb wave scanning experiment scheme is developed, and a scanning experiment system is set up. The composite plate is scanned and detected from two mutually orthogonal directions. The correctness of the finite element model is verified by comparing the simulation and experimental results. Finally, the defect images in the scanning area are obtained according to the probability damage algorithm. The imaging results indicate that the air-coupled Lamb wave defect imaging method using scanning detection can effectively identify the size, shape and damage degree of composite plate defects.