Welding in the World

, Volume 54, Issue 9–10, pp R286–R291 | Cite as

Numerical Analysis of Forming Mechanism of Hump Bead in High Speed GMAW

  • Ji Chen
  • Chuan-Song Wu
Peer-Reviewed Section


A thorough understanding of the physical mechanisms responsible for humping bead formation in high speed GMAW (gas metal arc welding) is essential to improve the welding productivity in today’s competitive manufacturing industries. Based on the experimental observing results, a mathematical model is developed to quantitatively analyze the forming mechanism of humping bead for high speed GMAW, considering both the momentum and heat content of the backward flowing molten metal in weld pools. One term related to the momentum of backward flowing molten metal is added to the equation of the weld pool surface deformation, and the heat content of overheated droplets is distributed within the layer covering the whole pool. The humping bead forming process and its dimension and 3-D geometry are numerically simulated under some welding conditions. It is found that the model can describe and characterize the humping formation in high speed GMAW quantitatively.

IIW-Thesaurus keywords

High Speed GMA welding Mathematical models Reference lists Weld shape 


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Copyright information

© International Institute of Welding 2010

Authors and Affiliations

  • Ji Chen
    • 1
  • Chuan-Song Wu
    • 1
  1. 1.Institute of Materials JoiningShandong UniversityJinanP.R. of China

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