Characterization of resin-injection repair of impact damage in polymer matrix composite

Resin injection repair of impact damage in polymer matrix composites is studied using an in-house developed repair methodology. Carbon fiber reinforced polymeric composite specimens were impacted for three levels of impact damage (23 J, 35 J and 51 J - typical of low energy, medium energy, high energy) using a drop tup test rig and the damage zone was characterized using ultrasonic C-scan technique. The impact damaged specimens were repaired using a resin infiltration method. The selection of low viscosity room temperature curing resin, and process parameters such as resin injection pressure and vacuum levels to be maintained were studied to arrive at optimum repair method. The tension, compression strength of laminates prior to impact and post-impact as well as post-repair was studied to assess the quality of repair method. The results indicate that the chosen resin injection repair is effective for the repair of low energy impact damage but not in the case of medium and high energy impact damage.