Numerical simulation of humping phenomenon in high speed gas metal arc welding
Numerical simulation of humping phenomenon in high speed gas metal arc welding
Ji CHEN1,2, Chuan-Song WU2()
1. State Key Lab of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin 150001, China; 2. Institute of Materials Joining, Shandong University, Jinan 250061, China
It is of great significance to obtain a thorough understanding of the physical mechanisms responsible for humping bead phenomenon in high speed gas metal arc welding (GMAW) in order to raise welding efficiency. Experiments were conducted to observe the weld pool behaviors in high speed GMAW, and it was found that both the severely deformed weld pool surface and strong backward flowing play a dominant role in humping bead formation. In this study, a mathematical model is developed to quantitatively analyze the forming mechanism of humping beads for high speed GMAW through considering both the momentum and heat content distribution of the backward flowing molten metal inside the weld pool. The transient development of temperature profiles in the weld pool with severe deformation demonstrates the humping bead forming process under some welding conditions. The predicted and measured humping bead dimensions are in agreement.
. Numerical simulation of humping phenomenon in high speed gas metal arc welding[J]. Frontiers of Materials Science, 2011, 5(2): 90-97.
Ji CHEN, Chuan-Song WU. Numerical simulation of humping phenomenon in high speed gas metal arc welding. Front Mater Sci, 2011, 5(2): 90-97.
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