復(fù)合焊縫成形的影響
(1. 華中科技大學(xué) 光電子科學(xué)與工程學(xué)院 武漢光電國(guó)家實(shí)驗(yàn)室，武漢 430074；
2. 中國(guó)兵器科學(xué)研究院 寧波分院，寧波 315103)
摘 要: 系統(tǒng)研究激光功率、電弧電流和熱源間距對(duì)10 mm厚AZ31鎂合金激光−MIG (Metal inert gas) 復(fù)合焊接工藝穩(wěn)定性和焊縫成形的影響規(guī)律。結(jié)果表明：實(shí)現(xiàn)最大激光−電弧協(xié)同效應(yīng)的最優(yōu)熱源間距為3 mm；復(fù)合焊接熔深決定于激光功率；MIG電弧電流對(duì)焊縫寬度有顯著影響，但是對(duì)焊接熔深影響有限；在優(yōu)化的工藝參數(shù)下，激光−MIG復(fù)合焊接能夠有效消除鎂合金激光焊縫中存在的表面成形缺陷，焊接速度提高50%；與MIG焊接相比，復(fù)合焊接熔深提高近10倍，電弧燃燒和熔滴過(guò)渡穩(wěn)定性大幅度提高；因而激光−MIG復(fù)合焊接是鎂合金焊接的一種有效方法。
關(guān)鍵字: 鎂合金；復(fù)合焊接；激光焊接；電弧焊接；焊縫成形
laser-MIG hybrid welding of AZ31 magnesium alloy
（1. School of Optoelectronics Science and Engineering, Wuhan National Laboratory for Optoelectronics,
Huazhong University of Science and Technology, Wuhan 430074, China;
2. Ningbo Branch of China Academy of Ordnance Science, Ningbo 315103, China）
Abstract:Laser-MIG (Metal inert gas) hybrid welding with 10 mm thick AZ31 magnesium alloy was carried out and the effects of laser power, arc current and laser-arc distance on the weld shape were studied. The results show that the optimal laser-arc distance that has the maximum laser-arc synergic effect is 3 mm and the penetration depth of hybrid weld depends on the laser power. The arc current has an evident effect on the bead width but only a little influence on weld penetration depth. Under the optimal welding parameters, the laser-MIG hybrid welding can obtain good welds without morphological defect and the welding speed increases to 1.5 times as that of laser welding. Compared with MIG welding, the droplet transfer of hybrid welding is more stable and the weld penetration depth increases to nearly 10 times. The study demonstrates that the laser-MIG hybrid welding is an effective welding process for magnesium alloy.
Key words: magnesium alloy; hybrid welding; laser welding; arc welding; weld shape
