Droplet transfer behavior of high strength aluminum alloy CMT+P arc additive manufacturing

被引:0
|
作者
Zhang Z. [1 ]
Gou Q. [1 ]
Lu X. [1 ]
Wang H. [2 ]
Cao Y. [1 ]
Guo Z. [1 ]
机构
[1] College of Aeronautical Engineering, Civil Aviation University of China, Tianjin
[2] Mechanical Science and Engineering College, Tianjin University of Technology and Education, Tianjin
关键词
arc additive manufacturing; cold metal transfer plus pulse; droplet transfer; flow field; high strength aluminum alloy;
D O I
10.7527/S1000-6893.2022.27881
中图分类号
学科分类号
摘要
The new technology of Cold Metal Transfer and Pulse(CMT+P)composite arc realizes the fine control of arc energy,and provides a reliable guarantee for obtaining high-quality arc additive formed parts. However,the droplet transfer behavior in the synergistic action of CMT and pulse is not clear,which impacts heavily on the stability of additive process and forming quality. Based on the theory of hydrodynamics and electromagnetism,this paper takes high-strength aluminum alloy as the research object,adopts dynamic grid technology and interface tracking technology,and comprehensively uses numerical simulation and in-situ observation test methods to clarify the evolution mechanism of droplet transfer behavior in the process of CMT+P arc additive of high-strength aluminum alloy. The results show that the simulation results are highly consistent with the experimental results. When the average wire feeding speed is 5 m/s,the droplet transfer of high-strength aluminum alloy CMT+P arc additive process presents a mixed transition mode of short-circuit transition in CMT stage and one pulse one drop ejection transition in pulse stage. The metal liquid bridge formed by the mechanical tension of the fuse in the short circuit stage can effectively avoid the splashing of molten droplets and improve the forming quality. In the pulse stage,the droplet is coupled by electromagnetic force,surface tension,Marangoni force,gravity and plasma flow force to form a static area. The velocity converges or diverges in the static area,forming the characteristics of upward and downward reverse flow velocity,which further affects the stability of droplet transition. © 2023 AAAS Press of Chinese Society of Aeronautics and Astronautics. All rights reserved.
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共 27 条
  • [21] NICHOLS B D., Volume of fluid(VOF)method for the dynamics of free boundaries[J], Journal of Computational Physics, 39, 1, pp. 201-225, (1981)
  • [22] VOLLER V R, PRAKASH C., A fixed grid numerical modelling methodology for convection-diffusion mushy region phase-change problems[J], International Journal of Heat and Mass Transfer, 30, 8, pp. 1709-1719, (1987)
  • [23] Heat transfer,fluid flow and electromagnetic model of droplets generation and melt pool behaviour for wire arc additive manufacturing[J], International Journal of Heat and Mass Transfer, 148, (2020)
  • [24] ZHAO W Y,, CAO X Y,, DU X W,, Et al., Numerical simulation of heat and mass transfer in CMT-based additive manufacturing[J], Journal of Mechanical Engineering, 58, 1, pp. 267-276, (2022)
  • [25] CHEN G Q, LIU J P,, SHU X, Et al., Numerical simulation of keyhole morphology and molten pool flow behavior in aluminum alloy electron-beam welding[J], International Journal of Heat and Mass Transfer, 138, pp. 879-888, (2019)
  • [26] MURPHY A B., The effects of metal vapour in arc welding[J], Journal of Physics D:Applied Physics, 43, 43, (2010)
  • [27] MILLS K C., Cu-Al(Al bronze)[M]∥ Recommended Values of Thermophysical Properties for Selected Commercial Alloys, pp. 98-104, (2002)