下向MAG焊熔池在外加高频交变磁场下的自动成形控制

Automatic shaping control of molten pool in downward MAG welding under the condition of exterior high frequency alternating magnetic field

重力会造成下向MAG焊熔池失稳,影响焊缝成形性能。进行下向焊熔池力学行为以及熔池成形控制的分析与研究,提出利用电磁效应中电涡流力降低重力造成熔池失稳来模拟分析交变高频磁场、内部熔池电磁场、涡流场以及电涡流力对熔池的影响,并进行45°、90°下向焊试验,结果表明,高频交变磁场能够抑制熔池流淌,电涡流技术能够降低下向MAG焊熔池失稳。

Molten pool becomes instable because of gravity, and affects the appearance of weld. The mechanical behavior and shaping control of molten pool are analyzed and studied. A method which can make the molten pool unstable by reducing gravity making use of eddy current power in electromagnetic effect is proposed. The numerical simulation of the effect of the alternating high frequency magnetic field, electromagnetic field, eddy current field and eddy current power on molten pool is implemented. 45 degree and 90 degree downward welding experiments are carried out to verify the theory analysis. The results show that it is feasible for eddy current technology to overcome the instability of molten pool caused by gravity in downward metal active gas（MAG）welding.