The Cold Metal Transfer (CMT) welding process reduces the heat input in comparison to other MIG/MAG processes, claims Fronius. This uses a digital process control, which automatically detects short circuits and then helps to detach the droplet by retracting the wire; during welding, the wire moves forward and is pulled back again as soon as the short circuit occurs. As a result, the arcing phase is very short and the heat input reduced.
The company says CMT is suitable for welding steel joints using CO2and other shielding gases. It is also intended for use in the joining of steel and aluminium, as the steel base material is only wetted by these braze-welded joints and does not melt. This means it meets the requirements for use in the automotive industry.