Laser-MIG hybrid welding of 5052 aluminum alloy assisted by magnetic field with three waveforms was performed. The results showed that compared to that without a magnetic field (NMF), the weld depth was increased by 46.3%, 45.1% and 22.4%, respectively, with the sequence of the static magnetic field (SMF), Triangular-wave magnetic field (TWMF) and Sine-wave magnetic field (SWMF), due to different dispersing effect of magnetic fields on welding plasmas. The similar effect of magnetic field with three waveforms on stirring molten pool during solidification led to almost the same refinement of grain size and randomness of grain orientation. Additionally, magnetic fields were found to improve stability of keyhole, prolong solidification time of molten pool and provide more escaping channels of bubbles, the porosity rate of weld was thus reduced from 7.80% to 3.46%, 2.11% and 0.82% when SMF, TWMF and SWMF were employed, respectively. As a result, the hardness and tensile properties of fusion zone under magnetic field with three waveforms were significantly improved and the highest tensile strength was obtained in the case of SWMF. Among the three types of magnetic fields, SWMF was the best in terms of reducing the weld porosity and increasing the tensile strength.

在磁场辅助下以三种波形对5052铝合金进行激光-MIG混合焊接。结果表明，与静磁场（SMF），三角波磁场（SMF）的顺序相比，与没有磁场（NMF）的情况相比，焊接深度分别增加了46.3％，45.1％和22.4％。 TWMF）和正弦波磁场（SWMF），这是由于磁场对焊接等离子体的不同分散作用所致。凝固过程中，具有三个波形的磁场对搅拌熔池的相似影响导致晶粒尺寸的细化和晶粒取向的随机性几乎相同。此外，发现磁场可以改善小孔的稳定性，延长熔池的凝固时间并提供更多的逸出气泡通道，从而将焊接的孔隙率从7降低。当使用SMF，TWMF和SWMF时，分别为80％至3.46％，2.11％和0.82％。结果，在SWMF的情况下，具有三个波形的磁场下的熔合区的硬度和拉伸性能得到显着改善，并且获得了最高的拉伸强度。在降低三种类型的磁场中，SWMF在降低焊接孔隙率和提高抗拉强度方面是最好的。