This paper presents a viscoelastic temperature- and degree-of-cure-dependent constitutive model for an epoxy resin. Multi-temperature relaxation tests on fully and partially cured rectangular epoxy specimens were conducted in a dynamic mechanical analysis apparatus with a three-point bending clamp. Master curves were constructed from the relaxation test results based on the time–temperature superposition hypothesis. The influence of the degree of cure was included through the cure-dependent glass transition temperature which was used as reference temperature for the shift factors. The model parameters were optimized by minimization of the differences between the model predictions and the experimental data. The model predictions were successfully validated against an independent creep-like strain history over which the temperature varied.

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The aim of this article is to propose a macroscopic damage model, which describes the nonlinear behavior observed on woven composites with ceramic matrix. The model is built within a thermodynamic framework with internal variables. First of all, the efficiency of the model to describe the mechanical behavior of carbon fiber-reinforced ceramic matrix composites is outlined. Then, the predictive capability of the model is evaluated with the help of an alternate torsion test.

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Self-healing Ceramic Matrix Composites (CMCs) are good candidates for structural applications at high temperatures in oxidizing environments. These materials generate complex couplings between the thermal and mechanical fields. A multiphysics macroscopic model of both the mechanical behavior and the lifetime of CMC structures was proposed previously and was validated on the material's level. Here, its effectiveness in dealing with structural calculations with heterogeneous fields is analyzed and a non-local fracture criterion is proposed for high-gradient cases. All the simulations were carried out using Abaqus/Standard. The main interest of the model is its ability to predict the evolution of each of the material's mechanisms throughout the structure until final fracture. Another advantage is the ability to predict the fracture zone and the influence of indentations on the lifetime of the structure (damage tolerance analysis), both of which are very important for industrial developments.