Numerical investigation of low and high velocity impact behavior of cfrp thermoset and thermoplastic composites

Abstract

Impact resistance of carbon fiber reinforced polymer (CFRP) composites is a crucial property for aerospace structures exposed to both low-velocity impacts (LVI), such as tool drops and high-velocity impacts (HVI), such as bird or debris strikes. While thermoset (TS) composites are conventionally employed, thermoplastic (TP) composites are gaining attention due to their superior toughness, recyclability, and rapid processing. This study numerically investigates and compares the LVI and HVI response of woven CF/epoxy and CF/PPS laminates. Experimental impact tests on TP laminates were conducted to obtain material parameters and validate the models, whereas literature data were used for TS composites. Finite element simulations were performed in LS-DYNA using stacked-shell modeling and cohesive zone formulations to capture progressive damage mechanisms. The numerical models showed strong agreement with experiments, in terms of force, displacement, and energy absorption. Comparative results indicated that TP laminates absorbed more impact energy, exhibited smaller delamination areas and resulted in better impact resistance. These findings confirm the improved impact behavior of TP composites and their potential for impact-critical aerospace applications in addition to the other advantages.