Carbon dioxide gas shielded arc welding
Carbon dioxide gas shielded arc welding (referred to as CO2 welding) of the protective gas is carbon dioxide (sometimes using CO2 + O2 mixed gas). Due to the special influence of the thermal physical properties of carbon dioxide gas, the use of conventional welding power sources, the molten metal at the end of the wire will not be able to form a balanced axial free transition, usually requires the use of short circuit and droplet necking, thus, with MIG welding. Compared to the free transition, there are more splashes. However, if a high-quality welding machine is used, the parameters can be selected appropriately, and a very stable welding process can be obtained so as to minimize splashing. Due to the low cost of the protective gas used, the welding seam is well formed when the short-circuit transition is used, and the use of the welding wire containing the deoxidizer can obtain Liu-quality welded joints with no internal defects. Therefore, this welding method has become one of the most important welding methods for ferrous metals.