LOW-ENERGY REPETITIVE IMPACT IN CARBON EPOXY COMPOSITE

The reduction of the strength of a carbon fibre composite after impact is an important consideration in design. During routine maintenance activities and during operation, composite components may be subjected to repeated impact at localized sites. The resultant damage may seriously impair the subsequent mechanical performance of the composite. Thus, it is appropriate to investigate the effects of repeated impact on the residual strength of structural composite materials. The paper reports and discusses investigations made to identify and characterize the response of laminated carbon epoxy composites to low-energy repetitive impact. The residual strength after impact at various absorbed energy levels and different numbers of impacts has been studied for this material system by three-point bending. The investigated energies are in the range of 2-5 J and the maximum number of impacts is 405. Correlation has been found between a new variable comprising the logarithm of the product of number of impacts with the impact energy and the residual strength of this composite material system.