Low-velocity impact performance of aluminum honeycomb sandwich structures with composite face sheets

In this study, AL 3003 aluminum honeycomb cores with heights of 10 mm and 15 mm, which have been widely used in the automotive, aerospace, and defense industries in recent years, were employed. As face sheet materials, glass/epoxy, carbon/epoxy, and Kevlar (aramid)/epoxy laminated composites produced via the vacuum infusion method were utilized. The thickness of the composite face sheets was maintained at approximately 2 mm. Each sandwich composite specimen was fabricated by bonding 100 mm × 100 mm composite plates to the upper and lower surfaces of the honeycomb core using an epoxy-based adhesive. The prepared specimens were subjected to low-velocity impact loading at energy levels of 40 J, 60 J, 80 J, 100 J, 120 J, and 160 J using a CEAST Fractovis Plus impact testing machine. The experimental results indicated that the contact force decreased as the core height increased from 10 mm to 15 mm. Furthermore, glass- and Kevlar-based composites exhibited higher elastic energy absorption compared to carbon-based composites. The findings also revealed that both the type of face sheet material and the core height significantly influence the impact resistance of the sandwich structures, leading to different damage mechanisms under impact loading.