舱外服活门组件密封粘接研究

针对舱外服活门组件的密封粘接及工作环境要求，对HXJ-14、HYJ-51和FHJ-75三种增韧改性环氧胶黏剂开展了特种胶黏剂选型及典型环境性能研究、典型粘接样件粘接面结构设计和粘接工艺优化研究。结果表明：优选出的HYJ-51胶黏剂具有良好的粘接性能、耐交变温度循环性能、耐湿热环境性能、耐介质浸泡性能，满足舱外服活门组件密封粘接要求。在典型活门粘接组件中，控制聚四氟乙烯滑套和不锈钢阀体的配合间隙为0.1~0.15 mm，并且在不锈钢阀体粘接面上增加环形槽结构，可以有效减少粘接面的缺胶面积，避免形成贯穿性通道，提高活门组件粘接的密封可靠性。经过产品生产验证，实现了活门组件的可靠密封粘接，成功用于航天员舱外服生命保障系统。     

基于材料时变参量的挖补修理胶层内剪应力研究

以AS4/3501-6材料的挖补修理为研究背景，基于材料热、力学参数的时变特性，分别为补片和胶层建立了热-力-化学多物理场耦合的有限元模型，研究了不同挖补角度和胶层厚度对胶层残余剪应力的影响，探索了不同挖补修理设计方案下的修理过程中胶层残余剪应力分布。结果表明：挖补角度、胶层厚度的增大均会加剧胶层残余剪应力集中；减小挖补角度，可有效降低胶层残余剪应力及沿胶层径向平均剪应力梯度；3°挖补角度下胶层径向中点残余剪应力比15°下降低17%，径向平均剪应力梯度降低92%；减小胶层厚度，胶层残余剪应力减小但平均剪应力梯度增大，0.3 mm胶层厚度下胶层径向中点残余剪应力比1.5 mm下降低15%，径向平均剪应力梯度升高30%。经验证三维有限元模型及计算方法正确，为改进修理工艺、提高修复质量提供了依据。     

Nonlinear dynamic analysis of a multi-link manipulator with flexible links-joints mounted on a mobile platform

The present work theoretically demonstrates the dynamic analysis of a planar multi-link manipulator considering flexible links and joints mounted on a moving base. A nonlinear model of a multi-manipulator (N-links) has been developed accounting for an equivalent bi-directional mobile base. The nonlinear Euler-Bernoulli beam and spring-inertia/mass system have been introduced to demonstrate the flexibilities of links and joints, respectively. Modal analysis followed by trajectory analysis has been performed to investigate the behaviors of manipulator taking into account of accurate boundary conditions. Further, vibration characteristics, steady-state responses, and their stability at resonant situations due to joint motions and inertial coupling have been studied. Results of exploiting geometric and inertial coupling due to flexible arms on stability analysis of steady-state responses have been investigated and have been subsequently verified with the findings by directly solving the governing equations. Steady-state response characteristics to explore the dynamics of the multi-link manipulators under resonant states have been studied with the varying actuator mass, the flexibility of links, lifted payload, and joint parameters. The results thus obtained, deliver a useful insight into the position analysis and long-term behavior of multi-link flexible manipulators under harmonic hub-joint motions that shall further enable its proper vibration attenuation and control.     

考虑界面损伤的立式贮存药柱结构完整性研究

为了进一步结合实际分析固体火箭发动机药柱在立式贮存条件下的结构完整性，考虑推进剂/衬层界面损伤模式在复杂应力条件下具有多样性。以某型固体火箭发动机为例，与常规将衬层设置为粘接单元相比，模型在推进剂与绝热层之间设置粘接接触。对固体火箭发动机在立式贮存环境时经历固化降温、充气内压和重力载荷联合作用下有无界面损伤时的发动机进行仿真分析。结果表明:界面损伤的存在导致推进剂/绝热层界面这个薄弱环节更危险；该型固体火箭发动机药柱在充气内压增大过程中在人工脱粘层根部部位应力呈先增大后减小趋势；在充气内压达到0.085MPa之前，推进剂与绝热层之间考虑界面损伤时，推进剂在垂直于轴向的靠近人工脱粘层根部部分更容易损伤，之后则推进剂垂直于轴向的初始点更容易损伤。该结论可以为固体火箭发动机结构完整性精确仿真提供一定的指导。     

耐高温复合材料在火星探测器着陆器减速伞筒盖结构上的应用

针对火星探测器着陆巡视器减速伞筒盖结构在轨运行耐温度交变、辐照等空间环境和再入过程耐温度冲击性能需求,重点开展了筒盖复合材料耐温匹配性、力学性能、耐空间环境性能以及制件成型工艺研究。结果表明,选用J-168-1胶黏剂、J-245胶黏剂及T300/QY8911复合材料制备的试件通过各项性能试验考核,均能满足筒盖结构的设计指标要求。筒盖产品力学性能稳定,成型工艺可行性良好,最高瞬时使用温度可达200℃,经历空间环境模拟后力学性能保持率均在80%以上,耐高温、耐空间环境性良好。产品已成功装星发射,并在着陆巡视器落火阶段成功弹出分离,圆满完成使命。     

Integration of nanoindentation and finite element method for interpretable tensile properties:A cross-scale calculation method of uneven joints

Nanoindentation testing and its Reverse Analysis Method(RAM) show great potential in understanding the tensile properties of metallic alloys with various microstructures. Nevertheless,the tensile properties of heterogeneous materials such as nickel-based superalloy welded joints have not been well interpreted by combining the microstructures and nanoindentation results, due to their diverse and complex microscopic zones, which throws shade on the properties of separated zones in the material. He...     

铝蜂窝夹层板热管区域平面度控制方法研究

主要研究蜂窝板热管区域局部平面度超差的原因及控制方法。经分析,蜂窝叠块的尺寸精度以及胶膜固化后的厚度不均匀性是导致超差的主要原因,通过提高工装均压板的厚度,利用胶膜厚度的自适应性弥补零部件尺寸累积偏差,提高平面度,并对新方法下产品剥离、剪切强度进行测试,结果表明,该工艺方法可以在不影响产品力学性能的前提下大幅改善产品热管区域平面度。