以某游艇用的玻璃钢板为研究对象,设计超声导波检测试验平台,对其损伤进行检测.通过求解Lamb波在玻璃钢板中传播的频散方程,对比求解频散方程和实验两种手段绘制的频散曲线,分析频散方程应用于玻璃钢板的误差及原因;依据频散曲线的变化规律,适当改变激励信号频率,提取导波的单一模态对玻璃钢板中的损伤进行检测,实现了对损伤的较准确定位,为Lamb波应用于复合材料板损伤检测提供参考.
In this paper, the glass reinforced plastic plate of a certain yacht is studied, and the damage inspection experimental platform of ultrasonic guided waves is designed. We solve the dispersion equations of Lamb waves propagating in glass reinforced plastic plate, analyze the error and its cause when the dispersion equation is applied to the glass reinforced plastic plate by comparing two dispersion curves plotted based on the dispersion equation and the experimental result, respectively. According to the variation law of dispersion curves, the frequency of driving signal is appropriately readjusted to extract single mode lamb wave, meanwhile, the damage in the glass reinforced plastic plate can be detected and located accurately. This article presents reference to the composite materials plate damage detection by Lamb waves.