中文摘要：

运用有限元方法,分析了激光参量和铝板参量对铝板中激光激励Lamb波的影响。通过建立轴对称的激光辐射模型,计算出不同激光能量下的瞬态温度场分布。研究结果表明,激光能量过高会使铝板表面损伤,应控制激光能量,使其低于材料损伤阈值。随后固定激光能量,改变铝板板厚和激光光斑半径的大小,发现光斑半径减小时,Lamb波激发率提高,频带变宽,所含的频谱成分更丰富。

英文摘要：

The effects of the parameters of laser and aluminium plate on laser-induced Lamb waves in aluminium plates are analyzed by using finite element method.Through the establishment of axis-symmetry laser radiation model,transient temperature field distribution under different laser energy is calculated.Research results show that surface material will be damaged when the laser energy is too high.Therefore,laser energy should be controlled to be lower than material damage threshold value.While laser energy is fixed,plate thickness and laser beam radius are changed,it is found that excitation rate of Lamb waves increases and signal spectra band broadens and spectral component becomes richer when laser beam radius decreases.