Lanthanated tungsten is an oxidized lanthanum doped tungsten alloy, categorized as oxidized rare earth tungsten (W-REO). When dispersed lanthanum oxide is added, lanthanated tungsten displays enhanced heat resistance, thermal conductivity, creep resistance, and a high recrystallization temperature. These outstanding properties help lanthanated tungsten electrodes achieve exceptional performance in arc starting ability, arc erosion resistance, and arc stability and controllability.
Our lanthanated tungsten products include WLa10 (La2O3 1-1.2 wt.%), WLa15 (La2O3 1.5-1.7 wt.%), and WLa20 (La2O3 2.0-2.3 wt.%). CHEMETAL has 20 years’ manufacturing experience with W-REO. We are renowned for our continuous R&D of tungsten electrode products. Our lanthanated tungsten rods and machined parts meet various specifications and standards for a wide range of applications. We offer lanthanated tungsten electrodes for Tungsten Inert Gas (TIG) welding, resistant welding, and plasma spraying. We also provide large diameter WLa rods for use in semiconductor components and high-temperature furnaces.
WLa TIG welding electrodes are easily arc initiated and highly durable. WLa plasma spray electrodes exhibit excellent resistance to both arc erosion and high temperature and possess superior heat conductivity. WLa resistance welding electrodes have a high melting point and offer outstanding operational stability.
Lanthanated Tungsten | |
| WLa10 | La2O3 1 to 1.2 wt.% |
| WLa15 | La2O3 1.5 to 1.7 wt.% |
| WLa20 | La2O3 2 to 2.3 wt.% |
| Standard | ANSI/AWS A5.12/ISO 6848 |
| Diameter | .02”to 5” |
| Work Function | 2.8 eV to 3.2 eV |
Lanthanated tungsten is sintered from extremely pure powders of tungsten and oxidized lanthanum using our efficient, high-yield, powder metallurgy method. There are 3 key stages in the process: pressing, sintering, and annealing. Exacting standards are applied at each stage. The tungsten and lanthanum powders must be at least 99.95% pure; they must be composited evenly and uniformly; pressing must occur at 160-200 MPa; hydrogen sintering is conducted for 6 hours at an operating temperature of 2300-2400℃. Adherence to precise component quality and processing standards yields finished lanthanated tungsten rods and sheets of very fine grain size, with no cracking, flaking, or deformation.
Lanthanated Tungsten Electrode
Tungsten lanthanum electrode has proven to be a very promising material to utilize in further as electrodes. The valuable properties of oxide lanthanum allow Lanthanated tungsten electrode has well-balanced oxide evaporation and migration rate at a low electron work function. Therefore, Lanthanated tungsten electrode exhibit excellent arc starting, stability, and re-ignition, electrode life, as well as a low risk of weld contamination, especially when direct current (DC) welding is applied. Most importantly, lanthanated tungsten electrode has no radioactive hazard and works well in both DC and AC welding. Because of this, lanthanated tungsten electrode is considered as the prospective replacement of Thoriated tungsten electrode.
In addition, Lanthanated tungsten electrode has a better current carrying capacity and lower consumption (when operating the alternating current arc welding.) The lanthanated tungsten electrode (1.5% to 2% by weight of the La2O3) has become the optimum option for most applications in comparison to Thoriated tungsten and Ceriated tungsten.
Other Rare Earth Oxide Tungsten We Produce
CHEMETAL USA has the capacity to manufacture W-La2O3, W-CeO2, W-Y2O3, and other oxidized rare earth tungsten rods. They are mainly used as electrodes and cathodes in many applications. We are also dedicated to researching and developing qualified oxide rare earth tungsten flat materials.
Rare earth oxide doped tungsten electrodes, such as W-La2O3 and W-CeO2, possess many superior welding characteristics. Rare earth oxide doped tungsten electrodes represent the best properties among electrodes for Gas Tungsten Arc Welding (GTAW), which is also known as Tungsten Inert Gas (TIG) welding and Plasma Arc Welding (PAW). The oxides added to tungsten increased the recrystallization temperature and, at the same time, promoted the emission level by lowering the electron work function of the tungsten electrode.
Oxide Rare Earth Properties And Composition In Tungsten Alloy | ||||
| Type of oxides | ThO2 | La2O3 | CeO2 | Y2O3 |
| Melting point oC | 3050 (Th: 1755) | 2217 (La: 920) | 2600 (Ce: 798) | 2435 (Y: 1526) |
| Heat of decomposition. Kj | 1227.6 | 1244.7 | (523.4) | 1271.1 |
| Type of oxides after sintering | ThO2 | La2O3 | CeO2 (1690)oC | Y2O3 |
| Reaction with tungsten | Reduction of ThO2 by W occurs. forming pure Th. | Forming tungstate and oxytungstate | Forming tungstate | Forming tungstate |
| Stability of oxides | Lower stability | Higher stability | Reasonable stability at the electrode edge but lower stability at the tip | High stability |
| Oxide weight % | 0.5 - 3 | 1 - 3 | 1 - 3 | 1 - 3 |