| 引用本文: | 房玉超,杨子酉,丁睿,何景山.铝合金薄板电子束穿透焊熔池的数值模拟[J].哈尔滨工业大学学报,2017,49(11):30.DOI:10.11918/j.issn.0367-6234.201705147 |
| FANG Yuchao,YANG Ziyou,DING Rui,HE Jingshan.Molten pool behavior of full penetration EBW on 2219 aluminum alloy[J].Journal of Harbin Institute of Technology,2017,49(11):30.DOI:10.11918/j.issn.0367-6234.201705147 |
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| 摘要: |
| 为有效地控制电子束焊接后的焊缝成形，得到符合要求的焊接结构，本文基于电子束焊接熔池物理过程的分析，使用有限体积法(FVM)数值模拟软件Fluent，对2mm厚的2219铝合金电子束穿透焊的温度场和流场进行数值模拟，研究了电子束穿透焊时熔池的流动行为及规律.模拟结果表明，电子束焊接形成穿透型匙孔时，熔池中液态金属的流速大小和方向迅速发生改变，最大流速可以达到10 m/s；产生的金属蒸汽反冲压力会使熔池剧烈震荡，熔池中远离匙孔的液态金属在Marangoni对流的驱动下，使熔池上、下两部分形成了较中间部分更长、更不稳定的拖尾，同时促进了熔池宽度的增加；熔池宽度和熔池拖尾长度分别在35 ms、90 ms左右达到了稳定.模拟焊接熔池凝固后，正面焊缝有一定的余高，背面焊缝有一定的收缩，其表面焊缝形态与实际焊缝形态吻合良好.此外，通过对熔池中液态金属的流速分析，还可以得出结论：金属蒸汽反冲压力对熔池的驱动作用远大于重力和表面张力的影响.
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| 关键词: 电子束焊接 2219铝合金 数值模拟 穿透焊 流场 |
| DOI：10.11918/j.issn.0367-6234.201705147 |
| 分类号:TG 456.3 |
| 文献标识码:A |
| 基金项目: |
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| Molten pool behavior of full penetration EBW on 2219 aluminum alloy |
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FANG Yuchao,YANG Ziyou,DING Rui,HE Jingshan
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(State Key Laboratory of Advanced Welding and Joining(Harbin Institute of Technology), Harbin 150001, China)
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| Abstract: |
| In order to effectively control the welding seam formation during electron beam welding to meet the welding structure requirements, the physical process of molten pool during EBW was analyzed. A three-dimensional EBW model was employed to simulate the molten pool in full penetration welding based on finite volume method (FVM). The molten pool behavior and rules were discussed. The simulation results showed that when the keyhole is formed by electron beam welding, the velocity and direction of the liquid metal in the molten pool changes rapidly, and the maximum flow rate can reach 10 m/s.The molten pool was vibrated violently by recoil pressure during the welding process. The heated liquid metal away from the keyhole driven by Marangoni convection to increase the width of molten pool. The width and longitude of molten pool were stable at about 35 ms and 90 ms, respectively. After solidification, the weld reinforcement and the shrink appeared at the top surface and the reverse side. The bead shape abstracted from the simulation and experimental result showed similar evolution. Moreover, according to the analysis of fluid flow in molten pool, it can also be concluded that the driven force of recoil pressure was much greater than that of the gravity and surface tension.
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| Key words: electron beam welding 2219 aluminum alloy numerical simulation full penetration welding fluid flow |
