Study on Dynamic Mechanical Properties of Carbon Fiber-Reinforced Polymer Laminates at Ultra-Low Temperatures

This study uses experimental methods, theoretical research, and numerical prediction to study the dynamic mechanical properties and damage evolution of CFRP laminates at ultra-low temperatures. Based on the Split Hopkinson Pressure Bar (SHPB) device, we set up an ultra-low temperature dynamic experimental platform with a synchronous observation function; the dynamic mechanical properties of laminates were tested, and the damage evolution process was observed. The experimental results are as follows: The compression strength and modulus increase linearly with the increase in strain rate and show a quadratic function trend of increasing and then decreasing with the decrease in temperature. The damage degree of the dynamic bending sample increases obviously with the impact velocity and decreases first and then increases with the decrease in temperature. Based on the low-temperature dynamic damage constitutive, failure criterion, and interlayer interface damage constitutive of the laminates, a numerical model was established to predict the dynamic mechanical properties and damage evolution process of CFRP laminates at ultra-low temperatures, and the finite element analysis (FEA) results are consistent with the experimental results. The results of this paper strongly support the application and safety evaluation of CFRP composites in extreme environments, such as deep space exploration.