Drop-weight impact response of hybrid composites impacted by impactor of various geometries

Drop-weight impact response of hybrid woven composite plates was studied. Hybrid S2 glass-IM7 graphite fibers/toughened epoxy composites with two lay-up arrangements were impacted using spherical, flat-ended cylindrical and straight-line Charpy impactors. The time-histories of impact-induced dynamic strains and impact forces were recorded. The damaged specimens were inspected using ultrasonic C-Scan methods. Experimental results exhibited that hybrid composites with glass outer skins had higher resistance to impact compared to second type. It also delaminated more than hybrid composites with graphite outer skins. The 3-D dynamic finite element software, LS-DYNA, was then used to simulate the experimental result of drop-weight tests. Good agreement between experimental and FE results was achieved when comparing dynamic force, strain histories and damage patterns between experimental measurements and finite element simulations.