外加同步磁场对短路过渡CO2焊接过程的影响

短路过渡CO₂气体保护焊由于低成本、高效率、便于实现全位置焊接，广泛应用在工业制造领域，但是在焊接过程中，特别是在较高的焊接电流下，存在许多诸如飞溅，成形差，过渡过程不稳定等问题. 文中提出了一种通过施加同步磁场来改善焊接中存在的问题的新方法. 研究了不同类型的燃弧段同步磁场对焊接过程的影响. 用激光作为背光，采用高速摄像系统拍摄焊接过程，观察熔滴过渡过程，计算熔滴的大小和过渡频率等. 结果表明，在纵向同步磁场的作用下，可以有效地减少燃弧时间；施加同步磁场后，熔滴过渡频率范围都得到不同程度的缩小，熔滴过渡过程更稳定，并且在纵向磁场I_m(LMF) = 200 A时，熔滴的过渡频率大幅增加；磁场作用下，带尖角的熔滴变为圆润无尖角的球形或椭球的熔滴，熔滴的尺寸减小.

Influence of synchronous magnetic pulse on short circuit transfer CO2 arc welding process

The short-circuit transfer of CO₂ gas shielded arc welding is widely used in manufacturing industry, but there are many problems such as spatter, poor formation,unstable transition, etc. in this welding process, especially during higher welding current. A new approach to solve the problems were put forward through applying a synchronous magnetic field. The effect of the synchronous magnetic field with different types on arcing phase was investigated. The short-circuit transfer processes were captured through high-speed camera system with laser backlight to observe the droplet transfer process, calculate droplet size and transfer frequency, etc. The experimental results showed that the droplet transfer frequency was increased, the short-circuit metal transfer process was more stable, the shape of droplet was changed evidently from a round or ellipsoid with sharp tip to flat end, and the dimension of droplet was reduced.