Utilizing Acoustic Emission for Studying Scaling and Layup Configuration Effect on Behavior of Glass/Epoxy Composite Materials Under Low-Velocity Impact

Composite structures under impact loading are prone to a variety of damage mechanisms such as delamination, fiber breakage, or matrix cracking. It is proven that the impact-induced damage mechanisms of composite materials are dependent on scaling (in-plane and out-of-plane) and layup configurations.  The present study has investigated the effect of scaling and layup configurations on the failure mechanisms of composite materials under low-velocity impact force using acoustic emission, C-scan and CT-scan tools. For this purpose, four samples with quasi-isotropic configurations of [45m/0m/90m/-45m]ns were manufactured, then they were loaded and acoustic signals were recorded. The three IS, PS, and SS samples were investigated based on D62624/D6264M ASTM standard test and the R sample had half of the in-plane dimension of them. The variables m and n vary according to the design plan. The obtained acoustic emission data were analyzed using sentry function, then C-Scan and CT-scan were utilized for damages’ size and location.   It was proven that scaling and layup configuration affect the type and intensity of damage mechanisms as well as mechanical behavior of the laminated composites. Furthermore, the acoustic emission method is shown as an indicator of scaling and layup configuration effects in glass/epoxy composite materials under the low-velocity impact.