Guided wave scattering at a delamination in a quasi-isotropic composite laminate: Experiment and simulation

Carbon fibre composite laminates are increasingly being used for aerospace structures due to their low weight and improved mechanical performance. Impact damage can cause delaminations below the visible surface of structure limited interlaminar strength. Guided ultrasonic waves detect characterize in laminates. The scattering A0 Lamb wave mode at an artificial delamination, located asymmetric depth a quasi-isotropic laminate, was investigated. Full field non-contact laser measurements were visualise trapping scattered waves. A three-dimensional finite element model developed validated against experiments. influence delamination shape on guided studied. Small variations significantly affected interference pattern top but had effect outside delamination. Delamination found strongly angular direction amplitude Implications structural health monitoring discussed.