There is no denying that aluminium is one of the most abundant metallic elements on earth and one of the most widely used nonferrous metals. Aluminium is common in manufacturing industries such as aerospace, automotive, construction, power transmission, and transportation because it is readily available, affordable, durable, strong, and lightweight.
However, much like steel and titanium, aluminium has gained a reputation of being difficult to wield, especially when you are using tungsten arc welding. However, this doesn’t mean that it is impossible to weld the metal easily and successfully.
All you have to do is understand the metal’s unique properties, figure out which techniques work best, and have the right tools. So, are you having problems welding aluminium? Here are a few tips to help you out.
Invest in a High-Quality Torch
When you are working with alternating current (AC), the energy in the form of heat is directed from the torch to workpiece and back to the torch. This means that the longer the bead or, the thicker the material, the more energy is returned to your torch and the hotter it will get.
A typical air-cooled torch is fine for short runs or thin sheets. Consider getting a high-quality water-cooled GTAW torch that remains cool even when you are running in the upwards of 600 amps. You don’t have to keep putting the torch down.
For the front end of your torch, ensure that it is has a glass lens with a no. 8½ -in gas lens nozzle that provides improved gas coverage and has advanced cooling capabilities.
Speed Is Critical
Aluminium welding experts at Edmo say that welding aluminium needs to be done pretty quickly. Once you start the welding process, you have to keep going because there is a danger of burning through the aluminium when it becomes overheated.
Your welding gun should keep moving along the weld, which is quite different from welding steel. Try everything possible to ensure that you don’t stop midway through welding.
Understand the Chemical Composition of Aluminium
Before you start welding aluminium, you need to understand its chemical composition to increase your chances of success. This metal has a rather unstable chemical composition that easily breaks up when under stress.
Quite often, when welding aluminium, it will react to the filler metal, which can cause unexpected cracking or breaking. To prevent this from happening, ensure that you choose a filler metal that has a chemical composition with much lower sensitivity to heat.
You should also keep in mind that aluminium has a relatively low melting point; hence, it is critical to use a GMAW process with pulsation ability to avoid cracking.
Remove the Oxide Layer
A thin oxide layer usually forms on the surface of aluminium naturally and melts at a relatively high temperature than aluminium itself. Therefore, proper pre-weld base metal preparation is critical when it comes to aluminium welding.
You need to take appropriate measures that will ensure that your aluminium is as clean as possible before you begin the welding process. Start by wiping the metal with a soft, lint-free cloth before you attack the oxide layer mechanically or chemically. There are lots of chemicals that you can use to get rid of the oxide layer.