Numerical Simulation Study of the Effects of Travel Speed on the Molten Pool Flow and Weld Bead Morphology of WAAM

doi:10.3901/JME.2022.10.103

Abstract

Abstract: The travel speed has important effects on heat and mass transfer as well as the weld bead forming in wire arc additive manufacturing (WAAM) process. In order to study the mechanism of these effects, a three-dimensional transient numerical model is developed, and the VOF method is employed to trace the free interface of the molten pool. The effects of travel speed on the heat transfer, molten pool flow and the single-pass weld bead morphology are discussed. Numerical simulation results show that with the reduction of travel speed, the heat accumulation and the volume of the molten pool, the peak temperature of the molten pool surface and the depth of arc crater are increased. At the same time, under the effect of the electromagnetic force and surface stress, the peak velocity of the molten pool surface is reduced, but the velocity of the internal molten pool is increased, the convection of the molten pool is more adequate with the reduction of travel speed. In addition, with the reduction of the travel speed, the width and height of formed weld bead are increased in varying degrees. The effectiveness of simulation’s results is verified by the experimental results under the same conditions. The results of this paper can provide theoretical support and basis for the process parameters’ controlling and adjusting of WAAM technology.

Key words: wire arc additive manufacturing, travel speed, molten pool, weld bead morphology, numerical simulation

CLC Number:

TG44

ZHOU Xiangman, WANG Boyun, YUAN Youlu, BAI Xingwang, TIAN Qihua, FU Junjian, DU Yixian. Numerical Simulation Study of the Effects of Travel Speed on the Molten Pool Flow and Weld Bead Morphology of WAAM[J]. Journal of Mechanical Engineering, 2022, 58(10): 103-111.

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