Reliability of damage mechanism localisation by acoustic emission on glass/epoxy composite material plate

This investigation focuses on the analysis of the Acoustic Emission (AE) wave propagation and velocity evolution in glass/epoxy composite materials according to the fibre orientation. In this work, several piezoelectric sensors were placed on a large composite laminate in the same direction in order to analyse by one measure, the velocity and wave attenuation over a large distance. Then, the measured velocity was compared with the theoretical values of velocity that have been identified by the theoretical model analysis. This last velocity was used during a three-point bending test to analyse the damage localisation on the plate according to the amplitude distribution model developed in the “Laboratory of Roberval at the University of Technology of Compiègne”. The results of the damage localisation on the specimens were compared to the visually observed damage (delaminating, cracks…) and were corrected on the basis of the amplitude correction. Finally, the error ratio of localisation without correction was quantified. The originality of this study was to use the AE results obtained on a large laboratory specimen in order to improve the AE testing on an industrial structure scale.