Experimental evaluation and multiscale simulation for the mechanical property of carbon fiber reinforced Vitrimer composites

Vitrimers resemble conventional thermosets, demonstrating comparable thermal stability and mechanical properties within operational temperatures. Beyond a critical temperature threshold, they display thermoplastic behavior due to their dynamic cross-linked networks. Despite their technological promise, current research inadequately addresses the systematic characterization of mechanical performance in vitrimer composites – a fundamental requirement for engineering applications. The mechanical properties of vitrimer composites can be designed by changing different stoichiometric ratios, this study systematically investigates the mechanical behaviors under tension, compression, and shear of Vitrimer-based composites at different epoxy/anhydride ratios, comparing them with traditional thermoset composites. The results demonstratethat Vitrimer composites with reasonable epoxy/anhydride ratio possess mechanical properties at room temperature that are comparable to traditional thermoset composite. To elucidate damage initiation mechanisms of the Vitrimer composite, a representative volume element (RVE) model was established, including matrix elastoplastic damage constitutive model and interface cohesive model, the interface parameters between fibers and matrix were obtained through inverse methods. Both simulation and experimental results show good consistency.