Tungsten (W)

Tungsten is a grey shiny metal with a very high density and features the highest melting and boiling point of all metals. Tungsten is mainly retrieved from Wolframite (FeMn)WO4) and Scheelite (CaWO4). Major resources are in P.R. of China, further resources can be found in the Russia and the CIS-states, Australia, Korea, Bolivia, Malaysia, Austria and others. More than 70 % of Tungsten is used for Tungsten carbides, alloys and pure metal, approx. 10-25 % is used as an alloy metal in steels and the rest serves for W-chemicals or other products.

Significant Characteristics and Applications:

• very high melting point, low vapor pressure
• very high density and good corrosion resistance in many acids, lyes and liquid metals
• over 500 °C rapid oxidization in atmosphere and starting from approx. 800 °C sublimation of W-Oxide
• under vacuum or inert gas excellent high temperature resistance

Pure-Tungsten, W-alloys and W-composite materials are used for filaments in bulbs, heating filaments, X-ray tube anodes, electrical switching contacts, heating elements, shielding, electro-discharge electrodes (EDM), welding electrodes (TIG), friction-stir welding tools (FSW), thermocouples, tool holders, counterbalance weights and others.

Important Types and Alloys:

• W 99,95 % (powder metallurgical)
• W-electrodes, doped: WT (ThO2), WL (La2O3), WC (CeO2), WZ (ZrO2), WY (Y2O3), WX (rare earth elements mixture)
• WRe3, WRe5, WRe25, WRe26

Tungsten Composite Materials:

• Tungsten-Copper WCu (type 10-50 % Cu)
• Tungsten-Silver WAg (type 15-70 % Ag)
• Tungsten High Density Alloy WSM (WNiFe; WNiCu, WNiFeMo)

ASTM Standard Specifications:
ASTM B760 (Tungsten Plate, Sheet, and Foil)
ASTM F288 (Tungsten Wire for Electron Devices and Lamps)
ASTM F73 (Tungsten-Rhenium Alloy Wire for Electron Devices and Lamps)
ASTM E696 (Tungsten-Rhenium Alloy Thermocouple Wire)
ASTM F269 (Standard Test Method for Sag of Tungsten Wire)
ASTM B702 (Copper-Tungsten Electrical Contact Material)
ASTM B631 (Silver-Tungsten Electrical Contact Materials)
ASTM B777 (Tungsten Base, High-Density Metal)

DIN EN ISO-Standards:
DIN EN ISO 6848 Arc Welding and Cutting – Non-consumable Tungsten Electrodes - Classification

Range of Products:
Strips, sheets, plates, wires, rods, tubes, sputtering targets, filaments, fabricated parts (screws, nuts and others), crucibles, high-temperature components, electrodes, contacts, fabricated components and assembling according to drawings.