Tungsten

tungsten-raw

Background Information

The word tungsten means “heavy stone” in Swedish. The chemical symbol for tungsten is W which stands for wolfram. The name came from medieval German smelters who found that tin ores containing tungsten had a much lower yield. It was said that the tungsten devoured the tin “like a wolf”. Pure tungsten metal was first isolated by two Spanish chemists, the de Elhujar brothers in 1783. Tungsten is a greyish-white lustrous metal, which is a solid at room temperature. Tungsten has the highest melting point and lowest vapor pressure of all metals, and at temperatures over 1650°C has the highest tensile strength. It has excellent corrosion resistance and is attacked only slightly by most mineral acids.

More Information on Tungsten

Detailed History: Tungsten & Tungsten Wire

Information on Tungsten Containing Minerals

How is Tungsten wire produced?

Tungsten Uses

Tungsten Machining Services & Capabilities

Tungsten Products

 

Properties:

Atomic Number74
Atomic Weight183.86
 Group Number6
 Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d4
CAS Registry Number7440-33-7
Atomic Volume9.53
Lattice TypeBody Centered Cube
Lattice Constant at 20 ºC, Angstroms3.1585
Natural Isotopes180, 182, 183, 184, 186
Density @ 20 ºC (gm/cc)19.3
Density @ 20 ºC (lb./cu. in.)0.697
Melting Point ºC3410
Boiling Point ºC5530
Linear Coefficient of Expansion per ºC4.3 x 10E-6
Thermal Conductivity @ 20 ºC (cal/cm/ºC/sec)0.40
Specific Heat @ 20 ºC (cal/gram/ºC)0.032
Electronegativity (eV) Pauling2.36
Electronegativity (eV) Sanderson0.98
Electronegativity (eV) Allred Rochow1.40
Electrical Conductivity, % IACS31
Electrical Resistivity @ 20 ºC (microhm-cm)5.5
Electrical Resistivity @ 227 ºC (microhm-cm)10.5
Electrical Resistivity @ 727 ºC (microhm-cm)24.3
Electrical Resistivity @ 1727 ºC (microhm-cm)55.7
Electrical Resistivity @ 2727 ºC (microhm-cm)90.4
Electrical Resistivity @ 3227 ºC (microhm-cm)108.5
Temperature Coefficient of Electrical Resistivity Per ºC (0 – 100 ºC)0.0046
Tensile Strength @ Room Temp., psi100,000 – 500,000
Tensile Strength @ 500 ºC, psi75,000 – 200,000
Tensile Strength @ 1000 ºC, psi50,000 – 75,000
Poisson’s Ratio0.284
Hardness (Mineral)7.5
Hardness (Vickers)3430
Hardness (Brinell)2570
 Reflectivity 62%
Total Emissivity @ 1500 ºC0.23
Total Emissivity @ 2000 ºC0.28
Working Temperature, ºC<1700
Recrystallization Temperature, ºC1300 – 1500