Synergistic effects of microscale variabilities on the thermo-mechanical behavior of a UD CFRP ply

Abstract

Attributed to the exponential growth in computing power, over the past two decades, computational micromechanics has emerged as an indispensable branch in the field of mechanics of composite materials. Within the framework of computational micromechanics, to predict the local stress–strain fields and damage profiles of a unidirectional (UD) composite ply, a Representative Volume Element (RVE) model needs to be generated by discretely modeling the building blocks of a composite ply such as fibers, matrix, and fiber-matrix interfaces. Besides, to accurately predict the observed experimental ply level stress–strain and damage behavior of a UD composite ply, the combined effect of various microscale geometrical and material parameters needs to be incorporated into the RVE model. Hence, the current research work presents a detailed modeling approach to incorporate several microscale parameters such as thermal residual stresses, random fiber placement, stochastic fiber-matrix interface properties, micro voids, and in-situ epoxy material behavior into the RVE model in a synergistic manner. Consequently, the stress versus strain curves and the damage profiles of the UD CFRP (Carbon Fiber Reinforced Plastic) composite ply is estimated and compared with the experimental data taken from the literature. The observed excellent agreement between experimental and numerical results suggests that the proposed computational micromechanical framework is a promising approach for predicting the ply level stress–strain and damage behavior of UD composites.