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论文类型：期刊论文

发表时间：2018-09-01

发表刊物：JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL

收录刊物：SCIE

卷号：25

期号：9

页面范围：995-1002

ISSN号：1006-706X

关键字：Pulsed laser-gas tungsten arc hybrid welding; Pulsed laser parameter; Dual heat source model; Weld pool shape

摘要：Based on the extended application of COMSOL multiphysics, a novel dual heat source model for pulsed laser-gas tungsten arc (GTA) hybrid welding was established. This model successfully solved the problem of simulation inaccuracy caused by energy superposition effect between laser and arc due to their different physical characteristics. Numerical simulation for pulsed laser-GTA hybrid welding of magnesium alloy process was conducted, and the simulation indicated good agreements with the measured thermal cycle curve and the shape of weld beads. Effects of pulse laser parameters (laser-excited current, pulse duration, and pulse frequency) on the temperature field and weld pool morphology were investigated. The experimental and simulation results suggest that when the laser pulse energy keeps constant, welding efficiency of the hybrid heat source is increased by increasing laser current or decreasing pulse duration due to the increased ratio of the weld bead depth to width. With large laser currents, severe spatters tend to occur. For optimized welding process, the laser current should be controlled in the range of 150-175A, the pulse duration should be longer than 1ms, and the pulse frequency should be equal to or slightly greater than 20Hz.