Impact Damage Evaluations in a Composite Laminate Using Guided Wave-Based Simulation

In the present paper, guided wave propagation along a composite plate was simulated using a 3D Finite Element (FE) model in order to characterize the potential damage due to impact. The wave is induced by a piezoelectric transducer. A pristine composite case and various cases representing different commonly observed impact damage modes were created. The wavefield contour and out-of-plane displacement data at different sensors between the pristine and damage cases were then compared to differentiate type of damage existing within the composite plate. It is found that observed wave propagation pattern and signals had significant difference between delamination cases and pristine one and the maximum amplitude of out-of-plane displacement of the plate during wave propagation increases with increasing delamination size when wave reaches and passes damaged area. The wave propagation in a composite plate with earlier stage damage, i.e., matrix cracks simulated in the present study, however, shows little difference compared to the pristine case for the wavelet frequencies studied herein.