负压激光焊接技术研究进展

Review of Laser Welding Under Subatmospheric Pressure

传统焊接方法难以满足大型构件厚板焊接对焊接效率和焊接质量的要求,而高功率激光焊接具有能量密度大、焊接效率高、焊缝深宽比大、接头质量高等特点,成为业界研究和应用的热点。然而近年来的研究发现,激光功率增大至一定程度,由于焊缝熔池的液体金属在激光作用下强烈蒸发而产生的金属蒸气和等离子羽烟对激光产生了吸收、折射、散射等屏蔽作用,使激光能量进入熔池小孔受阻,焊接熔深不再随激光功率线性增加。而负压环境却能使相同激光功率下的焊接熔深得到大幅度提升,获得成形良好的焊缝。根据近些年国内外学者在负压激光焊接方面的研究,综合介绍了负压环境下的激光焊接及其相关问题的研究进展,以期对国内相关研究发展起到促进作用。

Compared with traditional welding methods,high-power laser welding is characterized by high efficiency and good welding quality,especially in the welding process of thick plates.However,it was found out in recent researches when the laser power increased to a certain level,the welding penetration won’t get deeper any longer due to the absorption,refraction and the scattering effect of the plasma plume.That is generated by the evaporation of metal,and to prevent the laser beam from entering the keyhole.Welding under subatmospheric pressure is regard as an effective method and has an impressive promotion on both welding penetration and porosity defects.The development of the high-power laser welding under subatmospheric pressure,as well as some relevant issues are summarized according to recent researches.