Dynamic mechanical behavior of three-dimensional six-directional braided composites at ultra-low temperatures

Understanding the dynamic mechanical behavior of the three-dimensional braided composites at ultra-low temperatures is crucial for reliable applications in extreme environments, such as deep space exploration. This study systematically investigated the dynamic mechanical properties and damage evolution of three-dimensional six-directional carbon fiber reinforced polymer braided composites at temperatures down to −180 °C through combined experimental testing and numerical prediction. A dynamic experimental platform enabling in situ observation under ultra-low temperatures was established, and mechanical property tests were conducted across different strain rates and temperatures. By integrating micro-computed tomography data with elastic-plastic constitutive relations, a high-fidelity numerical model was developed to predict dynamic mechanical behavior more accurately, achieving excellent agreement with experimental results. These findings provide valuable insights into the structural design and performance prediction of three-dimensional braided composites operating at ultra-low temperatures.