DROPLET TRANSFER IN PULSED GAS METAL ARC-WELDING OF ALUMINUM

The droplet transfer mode is a critical element in the are welding pro cess. Multiple transfer modes have been identified, and the conditions under which they occur have been characterized. In the pulsed gas met al are welding (GMAW-P) process, droplet transfer mode is affected not only by welding voltage and current, but also by the pulsing paramete rs. In this work, experimental techniques were used to investigate the transitions from pulsed globular to pulsed spray to pulsed streaming transfer in GMAW-P of 1.2-mm 4047 aluminum welding wire. A new method for characterizing one-droplet-per-pulse (ODPP) operating conditions i s described and the transition from pulsed globular to pulsed spray tr ansfer is characterized. The roles of pulse frequency and duty cycle o n droplet transfer are explained.