Prediction mechanical properties of carbon fiber‐reinforced composites: A multiscale simulation framework based on bicomponent resin curing characteristics and interfacial properties

Abstract This study develops a multiscale simulation framework that integrates molecular dynamics (MD) simulations with the finite element method (FEM) to predict the mechanical properties of bicomponent (DGEBA/BDDE) resin/carbon fiber composites. The curing characteristics of the bicomponent resin were determined through MD modeling and simulations, and the influence of BDDE content on the interfacial energy of the resin/carbon fiber system was investigated. The interfacial vacuum layer between the resin and carbon fiber was modeled as a transversely isotropic elastomer, and its elastic constants were computed. These values were incorporated into the representative volume element (RVE) model to analyze the effects of varying interfacial thicknesses and fiber volume fractions on the macroscopic mechanical properties of the composites. Results indicate that increasing BDDE content decreases the mechanical performance of the resin system, with the 15wt% BDDE system achieving optimal interfacial energy. The computed elastic constants revealed significant modulus variations, ranging from the lowest out‐of‐plane shear modulus of 190 MPa ( G 13 ) to the highest in‐plane Young's modulus of 191 GPa ( E 2 ), spanning three orders of magnitude. The predicted Young's modulus from the multiscale framework showed an acceptable deviation from experimental data, confirming the framework's accuracy. This study presents an effective multiscale simulation framework for bicomponent resin, offering insights into interfacial property simulation and macroscopic elastic parameter prediction. Highlights The crosslinking model of bicomponent resin was constructed by MD. Consider the interface vacuum layer as a transversely isotropic elastomer. RVE finite element simulation parameters obtained from microscopic simulations. The system containing 15wt% BDDE showed the highest interfacial energy. The multiscale simulation framework can predict the elastic properties of CFRP.