Effect of welding speed on double pulsed GMAW of aluminum alloy

Using digital multifunctional welding power supply, double pulsed gas metal arc welding (DP-GMAW) of AA6061 aluminum alloy was carried out with different welding speeds, practically, defectfree welded joints were obtained. Numerical simulation was performed based on the collected welding parameters. The temperature and velocity fields in the weld pool were simulated, then the temperature gradient and cooling rate were calculated. The results indicate that when the thermal frequency of DP-GMAW was confirmed, the welding speed had no significant effect on the stability of welding process on condition that the welding speed was fit for the wire feed rate and welding current; the distance of weld ripples increased with the welding speed. With higher welding speed, DP-GMAW produced smaller temperature gradient, higher cooling rate, and higher hardness in the fusion zone.