【摘要】 空间桁架作为航天器结构的理想支撑平台,在深空探测、高分辨率对地观测等空间任务中得到了广泛应用。大型化、轻量化是航天器及其空间附属机构的发展趋势,但受地空运载能力与运载成本的约束,现有常规就地制造技术已无法满足大尺寸、高性能、复杂结构件的太空应用需求。在轨增材制造(在轨3D打印)技术可突破常规就地制造瓶颈,解决空间制备难题,实现低成本在轨建设。在轨增材制造是一种在微/零重力作用、高交变温差、强辐射等极端环境条件下的新型制造技术,由于发展时间较短,技术成熟度较低,诸多基础科学问题与关键技术问题尚待解决。空间大型桁架的在轨增材制造不同于传统地面增材制造,是地面增材制造技术的拓展与延伸。目前,在基础研究方面,国内外已开展了空间微重力环境下的熔融沉积成形增材制造试验,验证了微重力环境下熔融沉积增材制造的可行性。在成形装备方面,中、美、欧等国家或联盟均研制了适用于空间站舱内的熔融沉积增材制造样机,而针对空间大型桁架在轨增材制造的舱外装备,尚处于概念设计向工程样机转化的阶段。在成形工艺方面,受限于装备进展,在轨熔融沉积成形工艺性能研究较少;在模拟微重力环境中增材制造方面,针对大尺寸、长轴径比聚合物及其复合材料熔融沉积成形制件的力学性能各向异性,已通过材料改性、层间粘结热调控等方法得到不同程度的改进。本文系统总结了空间大型桁架在轨增材制造技术的发展现状与研究进展。针对在轨熔融沉积成形增材制造,归纳综述了空间微重力影响、在轨成形装备、成形工艺等关键瓶颈技术的研究现状,探讨了空间大型桁架在轨增材制造面临的挑战与发展趋势,为空间大型结构的在轨构建提供了理论基础与技术参考。更多还原

【Abstract】 Space truss is widely used in deep space exploration,high-resolution earth observation and other space missions. Nowadays,spacecraft and its attachments are developing into large-scale and light-weight. However,due to the constraints of space-earth carrying capacity and cost,the conventional on-site manufacturing technology cannot be satisfied by the space application requirements of large-scale,high-performance and complex structures. The on-orbit additive manufacturing( on-orbit 3 D printing) technology could break the technical bottleneck of on-ground manufacturing technologies to solve the space fabrication problems,and realize the low-cost construction.On-orbit additive manufacturing is a new fabrication technology of implement in extreme environment such as micro/zero gravity,high alternating temperature and strong radiation. Due to the short development time and low technology maturity,many scientific problems and key technical problems still need to be verified and solved. The on-orbit additive manufacturing of large space truss is an extension of the ground additive manufacturing technology. Up to now,in the field of basic research,the fused deposition modeling( FDM) technology in zero-g environment have been carried out successfully and verified the feasibility of additive manufacturing technology in microgravity. In the field of additive manufacturing equipment,the prototype of FDM aboard the space station has been developed by China,USA and Europe. However,the device applied for the onorbit additive manufacturing of large space truss outboard the space station is still on the concept situation. In the field of forming process research,there are few studies on the performances of on-orbit fused deposition modeling due to the restriction of equipment development. In the field of additive manufacturing in simulated microgravity environment,the anisotropy of mechanical properties of large-size,long-axial-diameter ratio polymers and their composites by melt deposition has been improved by material modification and heat control of interlayer bonding.This paper summarizes the research status and prospect of on-orbit additive manufacturing technology for large space truss. For the on-orbit FDM technology,it views the research status of the bottleneck technique such as microgravity effects,on-orbit equipment and forming process.The challenges and development trend of large space truss fabricated by on-orbit additive manufacturing are discussed. It could provide theoretical basics and technical references for the large structure of on-orbit fabrication research.更多还原