碳纤维复合材料贮箱内压和低温承载行为研究

碳纤维增强聚合物复合材料具有轻质高强的优异特性，是液氢液氧燃料贮箱的理想材料。然而液氢液氧燃料贮箱在服役时要承受极低温度载荷，复合材料贮箱箱体的低温结构可靠性尚未可知。开展了碳纤维/环氧复合材料缠绕贮箱结构在温度和内压载荷下的变形及损伤研究，分别进行了常温/低温抗渗漏测试，结合应变测量、声发射监测、氦质谱检漏等方法分别研究了内压以及低温工况对复合材料贮箱的应变分布及损伤泄漏状态影响机制。研究结果表明，封头与圆筒区域交界处易产生应变集中，低温载荷导致复合材料局部小幅度基体损伤及纤维/基体界面脱粘，但并未影响贮箱箱体承压性能和气密性。本研究可为未来大型航天器减质设计提供参考。

Performance of Carbon Fiber Composite Tank Under Internal Pressure and Low Temperature Loads

Carbon fiber reinforced polymer(CFRP) composite becomes an ideal candidate for the liquid fuel tank for its excellent characteristics of light weight and high strength. However, the liquid hydrogen/liquid oxygen fuel tank has to experience extreme low temperature in the service process, which brings uncertainties for the structural reliability. To solve the above problems, this paper carries out an experimental study on the damage and deformation behavior of CFRP wounded tank structure under the external load of liquid nitrogen cooling and internal pressure. Charging tests are carried out at both room temperature and low temperature (77 K), respectively. Helium mass spectrometry leak detection combined with strain measurement and acoustic emission testing are adopted to monitor the the strain distribution and damage leakage state of composite tank. The results show that strain concentration mainly occurs at the junction area between head and cylinder parts, and low temperature will lead to local matrix damage and fiber/matrix interface debonding for composite materials, while which will not affect the overall bearing performance and tightness of the CFRP tank. This study will provide references for the weight reduction design of spacecrafts in the future.