The low velocity impact response of auxetic carbon fibre laminates

The low velocity impact resistance of auxetic carbon fibre laminates has been compared to that of laminates with matched through-the-thickness modulus, but with Poisson's ratios of near zero and positive values. Four impact loads corresponding to major events in the static indentation response were examined and damage was assessed by ultrasonic C-scans, detailed fractography and measurement of residual properties. It was found that enhancements were seen in resistance to low velocity for the auxetic laminates, but only at low energy levels, indicating some degree of rate dependency. (c) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.