Modeling the temperature-rise behavior of 2D triaxial braided composites under impact loads

Due to their special geometric structure, the damage evolution and crack propagation behavior of twodimensional triaxially braided composite (2DTBC) is complicated and unique. In addition, under high-speed impact loads, the adiabatic heating-induced temperature rise may cause a phase change in the resin material. Therefore, the damage and failure behavior of 2DTBC under impact load is considered to be a dynamic and thermo-mechanical coupled problem. It is then necessary to develop an appropriate numerical method that is able to capture the temperature rise behavior of 2DTBC under various loading conditions. This study introduces infrared thermal imaging, quasi-static, low-velocity impact, and high-speed impact tests to measure the thermal response of the material during different loading conditions. Through the comparison against geometric configuration and full-field strain distribution images, the correlation between temperature-rise behavior with deformation and damage are systematically analyzed. An elastoplastic progressive damage constitutive model for fiber bundle was established with consideration of strain-rate dependency and thermal-mechanical coupling. A meso-scale finite element (FE) model for 2DTBC was developed to model the quasi-static and impact failure behaviors. Combing the experimental and simulation results, the temperature-rise behavior was clarified and the rate-dependent damage mechanism was revealed. The accuracy and applicability of the FE model were validated. The research results can provide theoretical basis and modeling tool for the practical application of this type of composites.