| 摘要: |
| 在太空环境中，航天器在轨运行时容易出现损伤，需开发航天器的在轨修复技术。本文面向在轨应用，开展2024铝合金典型缺陷的电子束填丝修复工艺研究。结果表明，采用合适的工艺参数可以实现孔洞缺陷和裂纹缺陷的良好修复成形效果，修复区无气孔、裂纹和夹杂等缺陷。修复区的微观组织主要由两侧的柱状枝晶和中心的等轴枝晶组成。热影响区的晶粒和析出相在热循环的作用下存在长大倾向。修复区显微硬度较母材降低，热影响区同样出现软化现象。对于裂纹缺陷修复试样，修复区抗拉强度达到269 MPa。热影响区在热循环作用下，呈现过时效与晶粒长大现象。研究结果表明低压电子束填丝修复工艺对铝合金缺陷的在轨修复具有可行性。 |
| 关键词: 2024铝合金 低压电子束填丝修复 成形特征 微观组织 力学性能 |
| 基金项目:国家自然科学基金面上项目（52175308）。 |
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| Study on Low Voltage Electron Beam Wire Filling Repair Technology of Aluminum Alloy for On-orbit Application |
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Liu Xiaochen Song Debin Wang Ting
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State Key Laboratory of Precision Welding Joining of Materials and Structures, Harbin Institute of
Technology (Weihai), Weihai 264209
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| Abstract: |
| In the space environment, spacecraft are susceptible to damage during orbital operations, making the development of on-orbit repair technology essential. This paper investigates the electron beam wire filling repair process for typical defects in 2024 aluminum alloy, specifically for on-orbit applications. The results indicate that appropriate process parameters can yield effective repairs and satisfactory formation of hole and crack defects, with no observed pores, cracks, or inclusions in the repaired zone. The microstructure of the repaired zone primarily consists of columnar dendrites on both sides and equiaxed dendrites in the center. In the heat-affected zone, the grains and precipitated phases tend to grow due to thermal cycling. The microhardness of the repaired zone is lower than that of the base metal, and the heat-affected zone also experiences softening. For the specimens with crack defects that have been repaired, the tensile strength of the repaired zone reaches 269 MPa. Under thermal cycling, the heat-affected zone exhibits the phenomena of overaging and grain growth. These results demonstrate that the low-voltage electron beam wire filling repair process is a viable method for the on-orbit repair of aluminum alloy defects. |
| Key words: 2024 aluminum alloy low-voltage electron beam wire filling repair forming characteristics microstructure mechanical properties |
