Advanced Fracture Modelling in Composite Materials: A Phase‐Field Approach Incorporating Elasto‐Plasticity and Nonlocal Effects

ABSTRACT This study presents a numerical investigation into the fracture behaviour of composite materials—an essential consideration for the reliable and sustainable design of lightweight structural components. To accurately capture their complex failure mechanisms, a phase‐field approach integrated with an elasto‐plastic material model was employed. The numerical framework utilised user‐defined subroutines (UMAT and UEL) within ABAQUS, complemented by additional simulations performed on the open‐source FEniCS platform. Deep Neural Network (DNN) is used to solve the phase field equations, and the results are compared to the standard FEA framework. Characteristic composite fracture features like crack deflection, kinking and nonlinearity are well presented. Given the inherent anisotropy and heterogeneity of composite materials, modelling their fracture behaviour remains challenging. Benchmark simulations, including force–displacement responses, were validated against published literature and demonstrated strong agreement. The diffuse nature of crack propagation—characteristic of the length‐scale‐dependent, nonlocal continuum mechanics underpinning the phase‐field method—was effectively captured and illustrated through plots showing phase‐field evolution relative to the distance from the crack centre.