Different MIG Welding Processes:
MIG (Metal Inert Gas) or also called GMAW (Gas Metal Arc Welding) uses an aluminium alloy cable as a joint electrode and stuffing material. The stuffing metal is added incessantly and welding with no filler-material is so not possible. Because all welding parameters are restricted by the welding machine, the procedure is also called semi-automatic welding.
The Metal Inert Gas process uses a straight current power source, with the electrode positive (DC, EP). By means of a positive electrode, the oxide coating is efficiently detached from the aluminium surface, which is necessary for avoiding lack of fusion and oxide addition. The metal is moved from the packing wire to the weld drop by magnetic forces as little droplets spray move. This gives deep penetration ability to the procedure and makes it probable to weld in all positions. It is significant for the excellence of the weld that the spray move is obtained.
The MIG-welding processes are, conventional MIG & pulsed MIG:
Conventional MIG (Metal Inert Gas) uses a steady electrical energy DC power source. Because the spray move is restricted to a certain range of arc current, the conventional MIG process has a lesser boundary of arc current (or heat input). This also limits the application of conventional MIG to weld material thicknesses over 4 mm. less than 6 mm it is suggested that backing is used to manage the weld bead.
Pulsed MIG (Metal Inert Gas) uses a DC power source with superimposed periodic pulses of high power. Throughout the little current stage the arc is maintained with no metal move. Through the high power pulses the metal is moved in the spray form. In this method pulsed MIG is probable to function with lesser average power and heat input compared to conventional MIG. This makes it probable to weld thinner parts and weld much more simply in hard welding positions.