High strain compressive impact testing was carried out using Split Hopkinson Pressure Bar for woven graphite/epoxy composites transversely and diametrically loaded at the impact energies of 67 J, 113J, 163 J, and 263 J. As it is hypothesized, the results show that thicker exhibit better elastic modulus and lower strain rate deformation. However, no thickness effect was observed on the energy absorption history for transversely loaded specimens even though energy absorption increases with increasing thickness for diametrically loaded specimens. The results show that energy absorption, elastic modulus, ultimate strength, and the strain rate increase with increasing applied energy as it is hypothesized. Most of the expendable energy for specimen damage returns to the system in the transverse loading case, with no visible incipient damage, while some portion of the energy absorption is consumed in the deformation process for the diametrical loading case. Smaller contact area gives larger deformation to the transversely loaded specimens resulting in lower elastic modulus, lower ultimate strength, higher energy absorption because of the energy release, and higher strain rate for the same thickness and impact energy.
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