Research Projects

Translaminar fracture in fibre reinforced composites is a complex process that involves multiple length scales and microstructural details. The proposed work aims to develop a multiscale model that can accurately predict the fracture of composites by accounting for the properties of constituent materials at both the micro and mesoscale. At the microscale, the fracture process involves mechanisms such as fibre breakage, fibre-matrix interface breakage, and matrix failure. At the mesoscale, they manifest as crack propagation, which is influenced by the microstructural details and constituent material properties. Modeling translaminar fracture behavior accurately for composites is challenging, as it requires accounting for multiple length scales and complex microstructure. The proposed multiscale model will overcome these challenges and provide valuable insights into the translaminar fracture of composites. Homogenization techniques are used to approximate the behavior of heterogeneous materials with microstructures that vary over multiple length scales. These techniques result in an effective or homogenized behavior of the material at a macroscopic scale, while accounting for the effects of microscale heterogeneity. We utilize homogenization to carry forward the physics of microscale mechanisms and their contribution in mesoscale behavior. Also, translaminar fracture is characterized by their unique and complex fracture surface due to pattern in fibre bundle pull out. Phase-field method can capture such complex phenomena, which are difficult to simulate using other techniques, making it a valuable tool for modeling complex crack trajectories. It involves solving a set of partial differential equations that model the evolution of a phase field variable representing the fracture energy. We will use the phase-field method to capture the crack trajectory in the composites. One key advantage is that it does not require a pre-defined crack path or mesh, as the crack evolves naturally as a result of the material properties and loading conditions. A micro-macro coupling will be established using heterogeneous multiscale finite element method (FE-HMM), a mathematical homogenization technique used to simulate the behavior of heterogeneous materials. In summary, the model aims to predict the translaminar fracture process in fibre reinforced composites by incorporating the mechanisms at the microscale (microproblem), translating them to the mesoscale properties (micro-macro coupling), and resulting crack propagation (phase field). This model will become a tool for virtual testing of composites and screening of their translaminar fracture properties by accounting for the constituent properties. It will also enable the identification of strategies to enhance the translaminar fracture properties. This can then be used to guide tailoring of constituent materials and optimize the design of fibre reinforced composites for specific applications.