TUNGSTEN – A Metal of Superlatives

Tungsten (W) is one of the so-called transition metals with the atomic number 74. The shiny gray metal is in a solid state at room temperature.

Tungsten is characterized by special physical and chemical properties:

• Heat resistance: After carbon, tungsten has the highest melting point of all elements at 3422°C. It has a boiling point of around 5,700°C. With these properties, the metal can withstand high temperatures and smelting and in addition, has a very low coefficient of thermal expansion
• Density: 19.3 g/cm³; the density of tungsten is almost as high as that of gold in the pure state.

We prepare our tungsten to perform perfectly in its specific applications. We can determine the following properties through the addition of various alloys.

• Machinability (such as cutting processes, formability, weldability)
• Microstructure and recrystallization behavior (recrystallization temperature, embrittlement, aging effects)
• Resistance: Tungsten has high resistance to acids. Even hydrofluoric acid and aqua regia are hardly able to attack tungsten at room temperature.
• Physical properties (such as melting point, vapor pressure, density, electrical conductivity, thermal conductivity, thermal expansion, heat capacity, and electron work function)
• Mechanical properties (such as strength, fracture behavior, creep resistance, and ductility)
• Chemical properties (corrosion resistance)

With their long service lives even at extremely high temperatures, our tungsten melting crucibles and mandrel shafts are able to withstand even quartz glass melts without difficulty. Thanks to the outstanding purity of our tungsten, we can reliably prevent any bubble formation or discoloration of the quartz melts.

Our tungsten is very popular for use in melting and solidification vessels in the field of sapphire crystal growth. Its high level of purity prevents any contamination of the sapphire crystal and its good creep resistance guarantees the product’s dimensional stability. Even at extremely high temperatures, the results of the process remain stable.

Because no other metal can compare with tungsten when it comes to heat resistance, tungsten is practically indestructible. For example, we use this material to manufacture high-temperature furnace components, lamp components, and components for use in the fields of medical and thin-film technology.

Tungsten has the highest melting point of all metals and therefore it is suitable for very high-temperature applications. It is also characterized by a uniquely low coefficient of thermal expansion and a very high level of dimensional stability.

For more information, please visit: http://www.samaterials.com/8-tungsten