Numerical analysis of transient keyhole shape in pulsed current plasma arc welding

Based on the characteristics of “one keyhole in a pulse” in pulsed current plasma arc welding (PAW), the transient variation process of weld pool in a pulse cycle is simulated through the establishment of corresponding heat source model. And considering the effects of gravitational force, plasma arc pressure and surface tension on the weld pool surface, the dynamic change features of the keyhole shape in a pulse cycle are calculated by using surface deformation equation. Experiments are conducted and validate that the calculated weld fusion line is in good agreement with the experimental results.