Tungsten, an element, is the material often used in electrodes for welding applications. If you're like many new welders, giving thought to the type of tungsten used wasn't something you've thought about in the past. However, when it's time to order from a tungsten supplier yourself, you may find yourself curious about the different options and wonder whether the tungsten you're used to working with is the best for the type of work you do. The various common tungsten types are described below:
Tungsten that is mined directly from the earth contains no oxide is not common in industrial applications, even though pure tungsten electrodes are usually cheaper than alternatives. Due to lack of oxide, arcs can wander so working with it takes a more dedicated hand. This type of tungsten is best for AC welds and not generally used for other kinds of welding.
You might already know something about thoriated tungsten, as it is perhaps the most commonly used choice for electrodes. This type of tungsten contains slightly less tungsten and some of the oxide thorium, which allows for lower working temperatures that keep the point sharp, stable and effective for work situations. Thoriated tungsten works quite well in DC applications to weld titanium, steel, nickel and thicker metals, but can be used for AC applications too. It is also slightly radioactive, of course, so ensure you're taking appropriate precautions and handling it while wearing the proper protective clothing.
Containing cerium oxide and tungsten-ceriated electrodes are versatile. Because they start up so quickly and there is little concern that the arc is going to wander, they can be used for both AC and DC projects. These electrodes work for thin metals like aluminum, but may at times be used for steel and other thicker metal sheets.
Rare earth is a large class of hybrid tungsten electrodes; each manufacturer that creates and uses these electrodes are obligated to label them appropriately so welders understand which oxides are in them and how much tungsten is being used. Because they are hybrids, they typically offer an extended arc life, higher current possibilities, and less splitting.
Whatever tungsten electrode you use, check with your work team and supervisors to ensure that the choice is acceptable. If you're using a different electrode than you're used to, test it out on a few sample metal sheets until you're sure that you've got a feel for what you can do with it