Experimental study of impact damage resistance and tolerance of composite sandwich panels

An experimental study of in-plane compressive behaviour of carbon/epoxy-skinned and E-glass/epoxy-skinned sandwich panels was conducted. For the former, two carbon/epoxy skin thickness combinations were 8/6 plies and 16/12 plies. Both cross ply (CP) and quasi-isotropic (QI) lay-ups were used in each combination. For the latter, two E-glass/epoxy skin thickness combinations of 8/8 and 16/16 plies were used with both being in a cross ply lay-up. The majority of sandwich panels were impact-damaged with their dominant damage mechanisms being characterised. All impact-damaged and baseline panels were in-plane compression tested. The effects of impact damage, lacking symmetry, skin thickness, skin lay-up and core density on CAI strength were examined.