Feasibility analysis of pulsed ultrasonic for controlling the GMAW process and weld appearance

The new method named as the pulsed ultrasonic-assisted GMAW (PU-GMAW) is studied in this paper, which was enforced by utilizing the pulsed ultrasonic to control the gas metal arc welding (GMAW) process. The main purpose of this paper is to study the feasibility of pulsed ultrasonic-assisted GMAW. Compared with the continuous ultrasonic-assisted GMAW (CU-GMAW), the influence of PU-GMAW on droplet transfer behavior and weld appearance is discussed. The results showed that the pulsed ultrasonic could assist GMAW. The PU-GMAW and the CU-GMAW both have their own advantages under different evaluation criterions. The droplet transfer cycles of the GMAW, the PU-GMAW, and the CU-GMAW were 199.5, 210, and 222 ms, respectively. The weld pool front angle of GMAW, PU-GMAW, and CU-GMAW are 17.75°, 12.3°, and 10°, respectively. The peak current of GMAW, PU-GMAW, and CU-GMAW were 300A, 350A, and 330A, respectively. Compared with the GMAW, the weld penetration and weld width of the CU-GMAW increased by 100 and 23.6%, respectively. The weld penetration and weld width of the PU-GMAW increased by 86 and 38.2%, respectively.