What Makes a Quality Tungsten Electrode?
Not All Electrodes are Created Equally
There’s no shortage of tungsten electrodes available from resellers who simply slap their label on the package. Some even consider this material a commodity and buy only based on the lowest price. That may be great for the purchasing department's budget, but it’s usually not so good for weld quality.
The majority of the tungsten electrodes on the market today come from China; most raw tungsten ore has come from China for years, as they have the largest deposits in the world. Most people are not aware of the U.S. government’s strategic decision to stop domestic mining and save its rare earth alloy deposits… for a rainy day.
No matter where the tungsten originates from, not all manufacturers are equal – not even close! Let’s take a closer look at some of the problems we’ve seen with sub-standard tungsten electrodes:
Varying Diameter – without strict adherence to O.D. (outside diameter) specifications, the tungsten electrode diameter can vary causing problems with the collet securely holding and positioning the electrode in the torch body.
Bent Electrodes – especially with smaller diameter tungsten electrodes. A bent electrode can cause problems when trying to grind a tip, and when inserting the electrode into a torch body.
Inconsistent Finish – spotty texture and uneven ground finish indicate a lack of production quality. A poorly textured finish can also contribute to inconsistent arc starts, and internal torch arcing problems.
Flaking Paint – tungsten electrodes are color-coded with a swab of paint on the end to distinguish one blend from another. When the paint flakes off, not only does it render the color-coding system useless, it can contaminate your weld.
That’s a run-down of what you can see, but what’s more important is the chemical make-up of the base material prior to extrusion. Tungsten electrodes are produced by mixing raw tungsten, chemical compounds, and specific dopiants to produce each blend (Thoriated, Lanthanated, etc.). The extrusion process, consistent mixing, and adherence to documented procedures are key to a high-quality end product… and ultimately, a high quality weld.
Bottom line, when considering tungsten electrodes, there’s a lot that can be different between brands. The best weld quality is only as good as the tools and consumables you have in the shop.