What’s the buzz about Tungsten? On the online welding bulletin boards over and over again I see questions having to do with tungsten electrodes for TIG/GTAW and Plasma Arc Welding: What is rare earth tungsten? Which tungsten is best? What’s the difference between thoriated/ ceriated/ green/ blue/etc? Will “all purpose” tungsten really work for everything? What about aluminum? Titanium? Stainless steel? Is thoriated tungsten really that dangerous? Does the brand of tungsten matter?
At Arc-Zone we almost always recommend ArcTime™ Hybrid All-Purpose tungsten. It is non radioactive and performs well on all machines and with all applications. But sometimes the tungsten (color) selection comes down to personal preference, or it may be spec’d out—this is often the case in automated welding processes or when working in certain government facilities, or anywhere that repeat-ability is imperative.
You probably know that electrodes are color-coded, and if you buy from a trusted manufacturer or supplier you’ll find that the colors and nomenclature adhere to the AWS and ISO standards:
AWS Class Color Alloying Element
EWP Green None
EWCe-2 Gray 2% Cerium **
EWLa-1.5 Gold 1.5% Lanthanum
EWLa-2 Blue 2% Lanthanum
EWTh-2 Red 2% Thorium
EWZr-1 Brown Zirconium
EWG Sky Blue Unspecified Rare Earth Alloys
**note: some manufacturers used to code the 2% Ceriated tungsten electrodes Orange, but Gray is now the AWS/ISO standard
And, if you buy from a trusted supplier or manufacturer you’ll also be sure to get a better quality tungsten. Factors including, how the tungsten is extruded from the earth, to how the various oxides are added in the manufacturing process, make a big difference in terms of purity and grain structure. High quality tungsten contributes to improved arc starting, better weld quality, and electrode longevity.
So in a nutshell, Yes, Brand does Matter.
A lot of folks prefer to buy products made in the U.S.A. With tungsten electrodes, that is nearly impossible. First, there is no tungsten mining in the United States and at present, the largest producers of tungsten are China and Russia. Second, GTP (formerly Sylvania) the lone U.S. manufacturer of tungsten electrodes has pulled out of the tungsten electrode manufacturing business. Whatever your supplier has left on the shelves is all there is. (Arc-Zone may still have few dusty boxes left, so let us know asap if you want some).
It’s not all bad news, however. There are some really great tungsten electrode options out there. CK Worldwide, a leader in top-quality TIG/GTAW welding accessories offers their own brand of tungsten. Diamond Ground Products also offers a complete line of top quality tungsten blends. Miller (formerly Weldcraft) offers a line of premium tungsten electrodes (you can read more about the Weldcraft tungsten at JoeWelder.com), and finally there’s Arc-Zone’s popular ArcTime™ Hybrid One Tungsten for All (TIG and PAW), the Tri-Mix tungsten, and the Ice-T™ Cryo Enhanced electrodes (for automated high production applications).
And if all these new choices confuse you, be sure to check out these publications from the technical experts at Arc-Zone.com:
What’s the Difference: Tungsten Electrodes, by Jim Watson explains the differences you’ll see between a quality tungsten electrode manufacturer and a substandard cheap import.
Guide to Tungsten Electrode Selection (.pdf), covers determining the best tungsten alloy for your welding application, selecting the proper size electrode, and guide to tungsten grinders.
Tungsten Electrodes: an Arc-Zone.com® Technical Focus Paper (.pdf) covers information on the history of tungsten mining, the properties of the various alloys, and tips for prepping the electrode for welding.
American Welding Society Safety and Health Fact Sheet on thoriated tungsten electrodes (.pdf)
Tungsten Image Credit: www.balticnordic.com