Thermoelastic mechanical process analysis of the laser-generated Lamb wave in thin fiber reinforced composite plate by numerical simulation

Abstract

A quantitative numerical modeling of laser-induced Lamb waves in thin unidirectional fiber-reinforced composite plate, transversely isotropic, is established by using finite element method (FEM). Taking into account the effects of thermal conduction, optical penetration as well as the finite width and duration of laser source, the transient temperature distributions are calculated. Applying the temperature distributions induced by the absorbed laser energy to structure analyses as thermal loading, the stress fields, the deformations of plate and the laser-induced Lamb waveforms are obtained. The mechanical generation process of Lamb wave is presented intuitively by analyzing the stress field propagation and the deformations of plate. The characteristics of Lamb waveforms caused by the anisotropic nature of specimen material, including amplitude and dispersive nature, are analyzed. This method provides insight to the generation and propagation of the laser-induced Lamb waves in thin unidirectional fiber-reinforced composite plate and establishes the quantitative relationship between the laser-induced Lamb waveforms and the laser input as well as the specimen parameters.