The low-velocity impact response of fiber-metal laminates

The low-velocity impact response of a series of glass fiber reinforced epoxy/aluminum alloy fiber metal laminates has been investigated. The influence of varying target thickness, plate diameter, and impactor radius has been studied and the results compared to those offered by plain composite samples. After testing, many samples were sectioned in order to highlight the failure modes under low-velocity impact loading. The FMLs absorbed significant energy in plastic deformation, tearing the metal layers and fiber fracture, and offered a superior impact resistance to the plain composite on which the FMLs were based. The perforation data were normalized by the areal density of the target and the superiority of the metal-composite hybrids remained in evidence. Increasing the target size, the plate thickness, and the indentor diameter resulted in an increase in the energy required to perforate the target. In contrast, impacting the square panels at the corner or along the edge of the target did not have a significant effect on the perforation response of the structures.