Effect of prestressed loading on low-speed impact performance for carbon fiber/epoxy resin composite laminates

Carbon Fiber Reinforced Polymer (CFRP) laminates habitually experience either tensile or compressive prestressing loads and are simultaneously susceptible to external low-velocity impacts in genuine operating scenarios. The current study establishes a meticulous model to elucidate the low-speed impact behavior of prestressed CFRP laminates, substantiated by finite element simulations. Initial validation of the model is accomplished by comparing simulated low-velocity impact scenarios without prestress against experimental data. Subsequently, the validated model is employed to simulate the low-velocity impact process under varying impact velocities and under both tensile and compressive prestress loads. It is demonstratively shown that tensile prestressing accentuates the extent of damage incurred by the laminate, a phenomenon that amplifies concomitantly with increasing impact speed. In contrast, compressive prestress is found to mitigate the laminate damage to a particular degree, albeit this mitigative effect is observed to diminish with escalating impact velocities. The findings derived from the investigation furnish pivotal data concerning the impact resilience of composite materials under practical working conditions and yield substantial engineering applicability for optimizing the design of related structures.