A Micromechanics-Based Processing Model for Predicting Residual Stress in Fiber-Reinforced Composites

摘要

The focus of this paper is to develop a micromechanics-based processing model that predicts the residual stress development in a fiber-reinforced composite during the curing process. The effective thermal and mechanical properties of the composite were computed in closed form using the concentric cylinder assemblage (CCA) micromechanics model. The effective composite thermal properties were used to solve the distributions of temperature and degree of cure (DOC) in the composite during the curing process through heat transfer analysis, where the cure kinetics was incorporated as an internal heat generation term. The solved temperature and DOC distributions were implement as pre-defined fields in the subsequent stress analysis of the curing process. The residual stress accumulation during the curing process was computed through the cure constitutive model that encompasses cure-dependent mechanical properties, thermal strains, and cure shrinkage. The proposed composite processing model was applied to predict the deformed shape of a nonsymmetrical laminate after the curing process. The composite was fabricated using the Vacuum Assisted Resin Transfer Molding (VARTsM) technique. The predictive capability of the proposed model is evaluated by comparing the computed curvatures of the panel with the experimental results.