Mig welding on aluminium is now becoming more and more common due to advances in technology in welding machines. While tig welding was generally considered the best for use on aluminium welding, it can now be undertaken very effectively by a mig machine. But bear in mind there may be times when tig is better used, but for the most part the introduction of pulse and double pulse technology will do the job at hand, giving equally good results that tig welding produces.
The main feature of double pulse technology is that it stabilises the heat source allowing great fusion but controlling it so as to avoid burn through, warping or distortion. As aluminium has a lower heat threshold, it melts quicker than most other metals, it still needs significant heat to form weld puddles. This will allow welding of very thin aluminium with full penetration without suffering burn through.
Similarly with stainless steel and mild steel (especially when welding thinner materials) there can be distortion if using high heat, but by using the double pulse system it allows for a colder weld, preserving its shape.
The pulse system allows for the standard DC current each second, whereas double pulse means there is a secondary current happening in tandem with this, but at much more frequent intervals, perhaps at 50 per second. This helps control the arc stability and ripple effect on a weld, giving a cleaner finish – something that is expected more from a tig welding process.
Another feature is that this system will work well with different diameters of welding wire, typically from 0.8mm to 1.2mm without having to change over feeds. This will save on production time and costs.
Double pulse technology in welding is a great asset to the auto repair and car restoration industry as it allows for far better results when you need a high heat source without distortion to the material being welded.