Evaluation of the effect of aging on mechanical, electrical and microstructural properties of CFRPs modified with CNT-doped veils

This study presents an approach to improve the performance of Carbon Fibre Reinforced Polymers (CFRPs) through the integration of Multi-Walled Carbon Nanotube (MWCNT)-doped copolyamide veils, focusing on the effects of aging and manufacturing techniques. Copolyamide veils containing 7.0 and 10.0 wt.% MWCNTs were introduced into the laminate structure using a novel pre-pressing step applied to unidirectional carbon fabric prior to the infusion process. This approach, which has not been previously reported, enables simultaneous enhancement of electrical conductivity and selected mechanical properties of CFRPs. The improvements are attributed to the exceptional adhesion achieved at the Carbon Fibre (CF)-copolyamide veil interface and the formation of effective conductive pathways across CF layers, in addition to the uniform distribution of MWCNTs within the veils. Furthermore, the results demonstrate that hygrothermal aging has a pronounced influence on the mechanical integrity of the modified CFRPs, leading to a reduction in mechanical performance associated with degradation of both the epoxy matrix and the copolyamide veils.