The Effect of Thermal Shock Cycling on Low Velocity Impact Behavior of Carbon Fiber Reinforced Epoxy Composites

In this research, we investigated the effect of temperature variation on low velocity impact response of woven carbon fiber reinforced polymer (CFRP) composites. Carbon fibers were weaved in twill 2/2 type and they reinforced the composite performance. We applied epoxy as composite matrix and then fabricated CFRP plates by using vacuum assisted resin infusion molding (VARIM) method. We performed thermal cycling shock experiment between -40 and +120 degrees C for 20, 40, 60 and 80 cycles. Then, we exposed specimens to the low velocity impact test for various thermal cycling numbers. The results showed that thermal cycling shock can improve or degrade the impact behavior based on post curing and debonding processes. Debonding possibly occurred since there was a coefficient of thermal expansion (CTE) mismatch between composite components. We also observed that the (room temperature tested) RT samples and the samples exposed to 80 cycles between -40 and +120 degrees C had the best and weakest performance, respectively. Finally, the increase of cycle numbers in thermal shock cycling process degraded the composite structure and decreased the impact performance of CFRPs.