Laser-enhanced metal transfer - Part II: Analysis and influence factors

Experiments were previously done to demonstrate that applying a relatively low-power laser to the liquid droplet could produce free flight transfers with welding currents below the transition one. In this paper, the effects of the laser intensity and are voltage on metal transfer process in laser-enhanced GMAW were discussed and analyzed. The enhancement of the laser was found to increase as the laser intensity increased. The larger laser intensity tended to help reduce the size of the droplet detached. The are voltage affected the metal transfer process through changing the current and changing the gap and possible time interval of the droplet development. A larger are voltage helped reduce the size of the droplet detached through an increased electromagnetic force. It also tended to provide a longer time to grow the droplet. In both cases, the chance for short-circuiting or repelled drop globular was reduced.