Decoupling control scheme for pulsed GMAW process of aluminum

A double-variable decoupling control scheme was proposed for GMAW-P process of aluminum helping to efficiently develop welding procedure. Weld pool width and arc length were both measured through vision sensing in welding process. Weld bead shape was improved by changing the current waveforms to adjust the heat input while the arc length was controlled to stabilize the welding process. An experimental system was developed to sense, observe and control the welding process real-timely. Experiments were conducted to verify the effectiveness of the scheme. The results show that good weld bead shape and stable welding process can be obtained through the double-variable decoupling control scheme without complex metal transfer control and considerable trial and error to identify suitable combinations of welding parameters in GMAW-P. This control scheme provides an alternative to obtain proper weld quality for GMAW-P.