Properties of Tungsten
- Tungsten lights get their name from the element in its filament.worklights image by Glenn Jenkinson from Fotolia.com
Two Spanish brothers, Juan José and Fausto Elhuyar, isolated tungsten from the mineral wolframite in 1783. In its pure form, tungsten turns steel into a super-alloy, strong enough for use in the heavy-duty turbine engines of jets. It appears in lamp filaments, television tubes and automobile distributors. The usefulness of the element drives its price. One pound of pure tungsten powder costs about $50. - With the naked eye, tungsten powder looks steel gray. As a solid, pure tungsten (99.9%) has a silvery white, tin metal appearance. You can cut a piece of tungsten with a hacksaw, or it can also be spun and forged. However, this metal is quite brittle in impure forms. Pure tungsten is best for applications that require flexibility, tensile strength and corrosion resistance.
- Tungsten is hard to tear. The metal withstands a tremendous amount of tension, or pulling force, before it ruptures. Its hardness makes tungsten materials popular with metalworkers. The Royal Society of Chemistry says the "painless" dental drill has strength at high speeds because it contains tungsten.
- Pure tungsten resists corrosion. However, the metal must be protected at elevated temperatures. It can oxidize when exposed to air. Despite this vulnerability, mineral acids only slightly affect it.
- Of all known metals, tungsten has the highest melting point, according to the University of Wisconsin's Periodic Table Live. If you heat tungsten to a high temperature and add sulfur, the metal will convert into tungsten disulphide, a highly adhesive, film-like, intact lubricant. At temperatures as high as 1,650 degrees Celsius, the metal maintains a high tensile strength, the highest of all known metals.
