Impact Studies in Glass Epoxy Laminates Containing Foam

Abstract

E glass epoxy laminates were made by a hand layup process. Laminates containing the central portion having either a 2 layer larger cell sized thicker width or a 3 layer thinner width flexible foam were also fabricated by the same route using a room temperature curing resin. Test coupons were cut from the fabricated laminates and impacted by a pendulum, having facility to load specific values for its mass, on the face of the laminate. Impacts were made by a single mass or a two stage impact operations involving preliminary hits, first by a smaller mass and then by a larger mass. The energy values associated with the process were computed. Macroscopy on failed test coupons was done to identify the dominant mode of failure and correlate the mechanical test data with failure processes. It is seen that foam bearing materials absorb increased impact energy compared to plain laminates and further, the cell-size/interfacial area of the foam plays a significant role in altering the fracture phenomena.