Effects of Low Temperature Thermal Cycling and Moisture on Izod Notch Toughness of a Glass FRP

摘要

Notched Izod impact tests were conducted on wet and dry specimens of a pultruded, glass fiber-reinforced polymer composite after thermal cycling between 25 and -50 deg C. Specimens were impacted following the application of 50, 150, and 300 thermal cycles. The results indicate that moisture initially had a beneficial effect on the notch toughness, probably due to a reduction in residual stresses from matrix swelling. After 300 thermal cycles, the beneficial effect of moisture was negated, likely due to an increase in damage from freeze/thaw expansion of the water, and a reduction in the overall moisture state in the composite. Further research is needed to quantify the damage accumulation during low-temperature thermal cycling.