Low-velocity impact, bending, and compression response of carbon fiber/epoxy-based sandwich composites with different types of core materials

This study focuses on the investigation of the effects of different core types on the low velocity impact, three-point bending and out-of-plane compression loading performance of sandwich composites. Three core materials were selected: Balsa wood, PVC foam, and Ayous wood. The facesheets of sandwich composites were produced by woven carbon/epoxy. Balsa and PVC foam are widely used in sandwich composites as core materials. In this study, Ayous wood, which is the lightest tree after Balsa, was used as core material in addition to traditional core materials. Woven carbon fiber fabrics with an areal density 200 g/m2 as reinforcement and epoxy matrix were used to produce the sandwich composite. Vacuum-assisted resin infusion molding method was used to manufacture composite panels. A number of tests under various impact energy levels for three different sandwich composites were conducted with Fractovis Plus impact testing machine in order to investigate the energy absorption capacity of sandwich composites. Maximum contact forces, absorbed energies, and the maximum deflections of sandwich panels were obtained for each impact energy level. Despite having the same facesheets, Ayous core sandwich composites possess a higher perforation threshold than Balsa and PVC foam sandwich composites. The perforation threshold of Balsa, PVC foam, and Ayous sandwich composites are 85, 72, and 170 J, respectively. In addition, the Ayous core sandwich composites have better bending and compression strengths. The bending strength of the Ayous sandwich composite is higher about six times than PVC sandwich composite and about two times than Balsa sandwich composite.