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Message No. 22522, Started by argeleintili on 06/21/16

Tungsten has many important uses and industrial applications. Several applications tungsten and its products are discussed here. The Word tungsten comes from Swedish language Tung-Sten, which means heavy stone. It is also known as volfram in Swedish.

The Word tungsten comes from Swedish language Tung-Sten, which means heavy stone. It is also known as volfram in Swedish. Its chemical symbol is W and atomic number 74. It is a hard, rare metal found naturally on Earth. It was first isolated as a metal in 1783 from its ores wolframite and Scheelite. This element shows remarkable properties of robustness. This is due to its high melting point in comparison to other elements.

Its density is comparable to that of uranium and gold i.e. 19.3 times that of water. Polycrystalline tungsten is brittle in nature with its inbuilt hardness. It is also very difficult to work with, Machining of tungsten requires special techniques and processes.

Alloys of tungsten have various industrial applications, such as X-ray tube electrodes, in TIG welding, super alloys, radiation shielding and bulb filaments. It serves a number of military applications due to its high density & hardness. It compounds are also used as industrial catalysts.

Natural Occurrence of Tungsten:

It's found in wolframite. Wolframite is a mixture of iron-manganese tungstate. They include the recently approved native tungsten.

Biological Occurrence:

It belongs to elements third transition series. However, it's still known to occur in biomolecules. It is also found in the metabolism of few naturally occurring species of bacteria and archaea. It is the heaviest element known to be used by any living organism. Tungsten interferes with body metabolism and is toxic to animal life.

Physical Properties of Tungsten Metal:

  • It is a hard steel-gray metal in raw form.
  • It is brittle and Machining Tungsten Process is tough.
  • In pure form, tungsten is malleable.
  • It involves forging, drawing, or extruding methods for machining.
  • It objects are machined by sintering process.
  • Highest melting point (3422 °C) among other metals of the periodic table.
  • It has the lowest coefficient of thermal expansion.
  • It has strong covalent bonds formed between tungsten atoms by the 5d electrons.
  • Alloy with steel have remarkable toughness.
  • Exists in two major crystalline forms: α & β.
  • Used in low-temperature superconducting circuits.

Chemical properties of Tungsten Metal:

  • Elemental tungsten resists attack by oxygen, acids, and alkalis.
  • Oxidation is in between −2 to +6.
  • Tungsten combines with oxygen to form tungstic oxide.
  • It forms tungstate ions in alkaline solution.
  • Tungsten carbides are produced by heating powdered tungsten with carbon.
  • It reacts strongly with chlorine to form tungsten hexachloride.
  • It belongs to the class of High Melting Point Metal.
  • Tungstate forms anions under neutral and acidic conditions.



If anyone have comments or suggestions on this post please feel free to let me know.

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Follow-up Messages (2)
where Tungstate stone is used? Can this stone be used in marine industry. ...
No. 22674, Posted by alfred3axel on 01/22/18, 22:21 PST.
I Have used tungsten steel for fine wood cutting. Is there a better alterna...
No. 22575, Posted by pulsator on 12/13/16, 20:26 PST.
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