Characteristic
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively combined with other elements in chemical compounds rather than alone. Its important ores include wolframite and scheelite.
Phase at STP:solid
Appearance:grayish white, lustrous
Melting point:3695 K (3422 °C, 6192 °F)
Boiling point:6203 K (5930 °C, 10706 °F)
Density (near r.t.):19.3 g/cm3
when liquid (at m.p.):17.6 g/cm3
Heat of fusion:52.31 kJ/mol
Heat of vaporization:774 kJ/mol
Molar heat capacity:24.27 J/(mol·K)
Application
Approximately half of the tungsten is consumed for the production of hard materials – namely tungsten carbide – with the remaining major use being in alloys and steels. Less than 10% is used in other chemical compounds. Because of the high ductile-brittle transition temperature of tungsten, its products are conventionally manufactured through powder metallurgy, spark plasma sintering, chemical vapor deposition, hot isostatic pressing, and thermoplastic routes. A more flexible manufacturing alternative is selective laser melting, which allows creating complex three-dimensional shapes.