Sensitivity of Crack Formation in Fiber-Reinforced Composites to Microstructural Geometry and Interfacial Properties

Abstract

Cracks mostly happen at the fiber/matrix interface and then propagate through the composites. Full cracks can accumulate, induce delamination, and lead to failure of the composite structure. In this work, we use interface-enriched generalized finite element method scheme to simulate two-dimensional microstructural representations of carbon fiber-reinforced polymer matrix composite. Fibers, matrix, and fiber/matrix interfaces are modeled by elastic, elasto-plastic damage, and cohesive zone constitutive equations, respectively. The constitutive equations are implemented in a C++/MPI framework and designed to be memory efficient and able to run the simulations entirely in parallel. The developed framework is used to investigate microstructural representations of fiber-reinforced composites efficiently. The sensitivity of the crack’s formation pattern and strain level to geometrical and material properties of the microstructural representation are investigated. Nine different microstructural representations of the composite considering matrix with linear and nonlinear behavior and a range of interfacial strengths are studied. It was found that for high interface strengths, the nonlinear matrix can have an influence on the crack’s location. The outcome demonstrated that for lower interface strengths, the matrix nonlinear behavior do not affect the cracks’ development pattern