Study on the Comparition of Properties between SPMIG and DPMIG Welding of AA6061 Aluminium Alloy

In order to improve the stability of SPMIG welding process, this paper fully utilized the characteristics that sine wave was the low-frequency modulation signal as well as the sine wave function was derivable for any order to make the energy change dE/dt smooth, thus improving the welding stability and welding joint performance. The tests for the SPMIG and DPMIG welding of AA6061 aluminium alloy were carried out, respectively. Then the test results of two kinds of welding methods in instantaneous current waveform, weld appearance, U-I diagram, probability distribution of current and voltage, weld hardness, microscopic structure of welds, and so on were compared, and the superiority of SPMIG was verified.