摘要

Two hybrid modes of laser-tungsten inert gas (TIG) hybrid welding (laser-leading and arc-leading) were tested on 2A14 Al-alloy, the influence on weld bead appearance, microstructure and hardness was analysed and the hybrid mechanisms were studied. The results show that the forming quality of weld surface in laser-leading mode is better than that of arc-leading mode, and the weld penetration is obviously deeper than that of arc-leading mode under the same welding parameters. Additionally, the weld surface in laser-leading mode is bright and with a little depression, while it performs dark and slight upheaval in arc-leading mode. The conclusion is drawn that the prime difference of the synergistic interaction between the laser and arc in hybrid welding is that laser breaks the oxidation layer firstly in laser-leading mode which leads to different utilization of the energy. As a result, the weld depth, weld width and hardness obtained by two hybrid modes are different.