Dynamic analysis of the ultrasonic-frequency pulsed GMAW metal transfer process

Current waveform control method was of great significance to welding quality of GMAW process. In order to study the influence of a novel control method of ultrasonic-frequency-pulse on metal transfer process, a high-speed-camera was employed for droplet monitoring, and two image processing algorithms based on MATLAB were proposed to extract the droplet size and position. Dynamic analysis based on pulsed GMAW in the mode of ‘one drop per pulse’ was carried out. The results showed that compared with the conventional pulsed GMAW, the ultrasonic-frequency-pulse promoted droplet falling speed without changing droplet size under the same stable condition, the droplet detaching mean velocity increased by 13 % at the maximum before the detachment, and the droplet driving force in peak time duration increased by 19.9 % at most after the detachment. The study helped to precisely control the pulsed GMAW metal transfer process.