基于非线性混频Lamb波的复合材料拉伸损伤研究

Study on tensile damage of composites based on nonlinear mixing Lamb wave

利用非线性混频Lamb波对复合材料板在拉伸受力过程中出现的不可见损伤进行了检测研究。建立了基于非线性混频Lamb波传播特性的有限元模型,研究了不同拉伸位移下的复合材料拉伸损伤与非线性混频Lamb波非线性响应之间的关系,以及复合材料板中拉伸损伤程度的不同对非线性混频Lamb波非线性系数的影响,并通过SNAP非线性超声检测装置对仿真结果进行了验证。结果发现:非线性混频Lamb波可用来检测拉伸损伤存在与否;在一定范围内,拉伸位移的增加将导致混频Lamb波的和频幅值以及和频非线性系数增加;借助混频Lamb波检测方法能够有效地对复合材料板的拉伸损伤情况进行评估。

The invisible damage of composite plates under tensile stress was detected by nonlinear mixing Lamb wave.A finite element model based on the propagation characteristics of nonlinear mixing Lamb wave is established.The relationship between the composite plate and the nonlinear response of nonlinear mixing Lamb wave under different tensile displacement and the influence of different tensile damage degree in the composite plate on the nonlinear coefficient of nonlinear mixing Lamb wave are studied.The simulation results are verified by snap nonlinear ultrasonic testing device.The research results show that the existence of strain can be detected by using nonlinear mixed Lamb waves;in a certain region,with the increase of tensile displacement,the sum-frequency amplitude of the mixed Lamb wave and the nonlinear coefficient of the sum-frequency gradually increase.The mixed Lamb wave detection method can effectively evaluate the tensile damage of composite plates.