Everyone eventually wants to weld on aluminum, as one of my students did by creating a Tig weld aluminum camper. Sometimes welding on steel all day gets boring. Making things out of aluminum is heaven on earth for some people. The question is, where do you start and how do I find out about this amazing metal.
Aluminum has many properties which are unique and have to be understood in order to fully weld and fabricate this material.
For example, the base metal becomes liquid when heated at 1,200 deg F as opposed to steel which becomes liquid around 2,700 deg F. However, aluminum has a unique ability to absorb heat and disperse it much more rapidly than that of steel. What that means is that it takes more time and initial BTUs (British Thermal Units) to get aluminum to that 1,200 deg temperature.
There are two preferred processes for welding aluminum. These are GTAW and GMAW. Mostly when we speak of beautiful aluminum welds, we are speaking of the GTAW process. GMAW has its place but since the aluminum filler wire is soft and expands when heated, we have to use a spool gun to weld with this process. Even though GMAW is not the preferred choice for cosmetics, it works well with thicker material and thin material that needs production quality because of the fast deposition rate.
There are certain alloys that contribute different strengths and desirable properties when added to aluminum.
1XXX series is weaker in enhancements because no great amount of alloys are added.
2XXX series has copper as its main alloy ( good for kitchenware, pots and pans)
3XXX series has manganese as its main alloy ( diamond plate work hardened sheet)
4XXX series has silicon as its main alloy ( only filler metal)
5XXX series has magnesium as its main alloy ( filler metal and work hardened sheet)
6XXX series has silicon and magnesium as its main alloys ( structural shapes, not bendable)
Learn more about this Tig weld aluminum camper at The welding Life blog!