The effectiveness of patch repairs to restore the impact properties of carbon-fibre reinforced-plastic composites

The present paper studies the low-velocity impact testing of carbon-fibre reinforced-plastic (CFRP) pristine and patch-repair CFRP panels. Firstly, effect repeated impacts on damage growth is considered at energies 7.5, 10.5 30 J. Secondly, such tests lead to a single-sided, panel being manufactured by removing 40 mm diameter central hole, act as ‘damaged area’, from parent then adhesively-bonding circular over hole so generated. Various diameters thicknesses for are employed and, in some cases, plug also used fill created removal composite. measured load versus time, displacement, traces compared. Further, extent location any interlaminar damage, i.e. delaminations between plies CFRP, caused event mapped using an ultrasonic C-scan technique. It shown that single-sided patch repairs can be very effective restoring performance damaged