Carbon fiber reinforced polymers (CFRP) are promising next-generation, lightweight materials for use in the automotive and aerospace industries. Unfortunately, the production cost of virgin carbon fiber is expensive, the manufacturing of CFRP parts is costly and wasteful, and the recycling of CFRP generally results in (1) the reduced mechanical properties of recycled carbon fibers (rCF) and (2) the incorporation of rCF into low-value composites. In efforts to improve upon these areas, we have recently developed malleable, healable, and recyclable vitrimer composites with milled rCF that have produced promising material and mechanical properties—this work aims to investigate and understand the damage/failure mechanisms of these materials. Herein, we utilize dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) to understand and observe the damage mechanisms that result in the mechanical failure of these materials. Further, we utilize this information to inform the development of a constitutive model. The model is based on a statistical description of the network structure. The principles of thermodynamics are then used to derive the constitutive behavior for CFRP.
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