面向火星探测的环氧形状记忆聚合物复合材料的性能研究

Study on epoxy-based shape memory polymer composites for Mars explorations

国家火星探测任务是建设航天强国进程中的重大标志性工程,是中国航天走向更远深空的里程碑工程.智能材料这种集材料、结构和功能于一体的先进材料将会对火星探测任务有所助力.形状记忆聚合物及其复合材料作为一种典型的智能材料,可在有效减轻载荷的同时实现自主变形,已经在地球同步轨道航天器的应用中崭露头角.因此有必要研究这种新型环氧基形状记忆聚合物复合材料应用于火星探测工程的可能性.首先,针对“天问一号”火星探测器的任务需求,设计了一个具有自释放功能的着陆平台国旗装置.其中的锁紧释放装置由碳纤维增强的形状记忆聚合物复合材料制成,分别从静态拉伸力学性能、动态热机械性能和形状记忆性能三个角度评估了空间辐照和长期存储对形状记忆聚合物复合材料的影响.其中,空间辐照包括γ射线和紫外射线,辐照剂量分别为5×10^(5)rad和23.6 kCal.长期存储分为低温-196℃、室温25℃和高温85℃存储30天,和低温-196℃存储457天两组实验.最后,从“祝融号”火星车所携带相机拍摄的照片可以看到五星红旗被成功释放,旗面平整、图案清晰.这说明所研究的环氧基形状记忆聚合物复合材料可成功应用于火星探测任务,未来有望以多种结构形式助力我国的火星采样返回乃至其它深空探测任务.

The Mars exploration mission is a major landmark project in building a powerful aerospace country and a milestone project for China's aerospace to move further into deep space.Advanced materials integrating structures with functions can do a favor.Shape memory polymers and their composites,as typical smart materials,can effectively reduce the payload while achieving autonomous deformation,and have been successfully applied to geosynchronous orbit.Therefore,we investigate the feasibility of applying these new materials to Mars explorations.Firstly,according to the requirements of the“Tianwen-1”mission,a self-deployable flag mechanism was proposed.Then from the perspectives of static tensile mechanical properties,dynamic mechanical analysis and shape memory performance,γand UV irradiation and long-term storage(temperatures(−196℃,25℃and 85℃)for 30 days and−196℃for 457 days)effects on shape memory polymer composites were investigated.Finally,according to the photos from the“Zhurong”rover,the National Flag of China was successfully released,and the flag pattern was clear and distinct.This shows that the shape memory polymer composites have been successfully applied to Mars explorations.In the future,it is expected to assist China’s Mars sample return program and other interstellar exploration missions in diverse structural architectures.