Investigation of UV aging influence on low velocity impact behavior of interply hybrid composites

This study investigates the effects of UV aging on the low-velocity impact behavior of hybrid and non-hybrid polymer composites, focusing on configurations using glass and aramid fibers. Composite samples were exposed to UV radiation for 0, 450, and 900 hours, and their impact properties were measured through flatwise and notchwise Charpy impact tests. Results showed significant degradation after 450 hours, with the glass/epoxy composite (P1) exhibiting a 35.37% reduction in flatwise impact strength from 65.77 kJ/m² to 42.51 kJ/m². Hybrid composites, such as the glass-aramid-glass configuration (H1), demonstrated improved resilience, with a smaller 29% decrease to 77.04 kJ/m². After 900 hours of exposure, all configurations showed partial recovery in impact properties, attributed to possible matrix reorganization; however, the overall impact strength remained lower than in non-aged samples. For instance, flatwise impact strength in P1 was reduced by 17.87% compared to control, while H1 and H2 hybrids experienced 17.07% and 21.75% reductions, respectively. These findings underscore that hybridization, especially with aramid, enhances resistance to UV-induced degradation, suggesting hybrid composites as superior candidates for applications in UV-intensive environments.