CFRP-钢胶接界面分层损伤区域的Lamb波传播特征研究

STUDY ON THE LAMB PROPAGATION CHARACTERISTICS IN THE DELAMINATION DAMAGE AREA OF CFRP-STEEL BONDING INTERFACE

针对CFRP-钢板的胶接界面分层损伤,通过仿真位移云图研究了Lamb波在分层损伤区域的传播反射过程,分析了分层长度对损伤回波的影响,设计试验对仿真结论进行了较好的验证;仿真提取分层上下界面节点的位移曲线分析了Lamb波高次谐波的产生原因,研究了分层深度位置、长度和激励幅值对非线性特征的影响。研究显示Lamb波对分层的退出端更加敏感且在分层区域较薄一侧有驻波产生,波的反射系数和非线性系数均随着分层长度的增加而呈振动变化趋势,当分层位置在近表面或者板厚的对称中心时,非线性特征较不明显。为Lamb波在CFRP-钢胶接界面分层损伤中的检测应用提供了重要参考。

For the bonding interface delamination damage of CFRP-steel plate,the propagation and reflection process of Lamb wave in the delamination area is studied by displacement cloud of simulation.The influence of the delamination length on the damage echo is analyzed,and then the test is designed to verify the simulation conclusion.The displacement curve of the upper and lower interface nodes of delamination is extracted by simulation,and the cause of the Lamb wave′s high order harmonic is analyzed.The influence of the depth position,length of delamination and excitation amplitude on the nonlinear characteristics is studied.The research results shows that Lamb wave is more sensitive to the exit end of delamination,and in the region of thin side of delamination area the standing wave is generated.The reflection coefficient and the nonlinear coefficient of the wave all show the trend of vibration with the increase of the delamination length.When the delamination locates near the surface or the symmetrical center of the plate thick,the nonlinear characteristics are not obvious.The research work of this paper provides an important reference for the detection and application of Lamb wave aiming at the delamination damage of CFRP-steel bonding interface.