Detection of Delamination in Laminated Plates Using A0 Mode of Acoustic Emission Waves

摘要

In this study,a simple method was presented to evaluate delamination in laminated plates.The characteristics of plate waves were investigated by using a formulation including stiffness coupling.For A0 mode,the wave velocity of laminated plates was largely affected by plate thickness,stack sequence and frequency.The acoustic emission (AE) signals were generated by pencil lead breaks,and these waves propagating in laminated plates with delamination were detected by the broadband width sensors.By the wavelet transform,the arrival time of AE waves of a certain frequency can be derived exactly and the wave velocity of A0 mode can be exactly calculated.The length of delamination in the laminated plates was derived by the difference of the arrival times.