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Tungsten single crystal 74W183.85
Discovered in 1783 by J.J. and F. Elhuijar at Vergara, Spain.
[Swedish: tung sten = heavy stone; wolfram is named after wolframite]
French: tungstètene
German: wolfram
Italian: wolframio (tungsteno)
Spanish: wolframio
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Description: Tungsten is generally obtained as a dull grey powder, which is difficult to melt. The bulk metal is lustrous an silvery-white, and resists attack by oxygen, acids and alkalis. Tungsten is used in alloys, to which it imparts great stength, in light bulb filaments and cutting tools.
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Metal single crystal properties
| State: |
single crystal |
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| Crystal structure: |
bcc |
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| Production method: |
Floating zone |
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| Standard size: |
diameter 8-12mm
thickness 1-2mm |
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| Orientation: |
(100), (110) and (111) |
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| Orientation accuracy: |
<2°, <1°, <0.5° or <0.1° |
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| Polishing: |
as cut, one or two sides polished |
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| Roughness of surface: |
<0.03µm |
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| Purity: |
99.999% |
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| Typical analysis (ppm): |
Ag < 0.10
Al 0.20
C 3.00
Ca 0.10
Cl 0.30
Co < 0.10
Cu < 0.10
Cr 0.15
Fe 0.60
H < 1.00
Mg 0.25 |
Mn < 0.10
Mo 4.00
N < 5.00
Na < 0.10
Ni 0.40
O 10.0
S 0.20
Si 0.70
Ta 1.00
V 0.50
Zr < 1.00
W balance |
Further Materials properties
| Crystal structure: |
(cell dimensions/pm), space group
b.c.c. (a=316.522), Im3m |
| X-ray diffractions mass absorption coefficients: |
CuKa 172 (µ/r) / cm2g-1
MoKa 99.1 (µ/r) / cm2g-1
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| Neutron scattering length: |
0.486 b/10-12 cm |
| Thermal neutron capture cross-section: |
18.3 sa / barns
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| Density: |
19.3 g/cm3 |
| Melting point: |
3406.85±20 °C / 3680±20 °K |
| Boiling point: |
5656.85 °C / 5930 °K |
| Molar volume: |
9.53 cm3 |
| Thermal conductivity: |
174 [300 K] Wm-1K-1 |
| Coefficient of linear thermal expansion: |
4.59 x 10-6 K-1 |
| Electrical resistivity: |
5.65x10-8 [300 K] Wm |
| Mass magnetic susceptibility: |
+4.0 x 10-9(s) kg-1m3 |
| Young's modulus: |
411 GPa |
| Rigidity modulus: |
160.6 GPa |
| Bulk modulus: |
311 GPa |
| Poisson's ratio: |
0.28 GPa |
| Radii: |
W6+ 62; W4+ 68; atomic 137; covalent 130 |
| Electronegativity: |
2.36 (Pauling); 1.40 (Allred); 4.40 eV (absolute) |
| Effective nuclear charge: |
4.35 (Slater); 9.85 (Clementi); 14.22 (Froese-Fischer) |
| Number of Isotopes (incl. nuclear isomers): |
29 |
| Issotope mass range: |
160 -> 190 |
Biological data
| Biological role: |
none |
| Toxicity |
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| Toxic intake: |
mildly toxic |
| Lethal intake: |
LD50 (metal, rat) = 2000 mg kg-1 |
| Hazards: |
Tungsten dust is a skin and eye irritant and an experimental teratogen. |
| Level in humans |
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| Blood: |
0.001 mg dm-3 |
| Bone: |
0.00025 p.p.m. |
| Liver: |
n.a. |
| Muscle: |
n.a. |
| Daily dietary intake : |
0.001 - 0.015 mg |
Total mass of element in average
[70 kg] person: |
c. 0.02 mg |
Geological data
| Minerals: |
Many minerals are known, and aluminium is present in many other minerals |
| Mineral |
Formula |
Density |
Hardness |
Crystal apperance |
| Ferberite |
FeWO4 |
7.40 |
4 - 4.5 |
mon., met. black |
| Scheelite |
CaWO4 |
6.10 |
4.5 5 |
tet., vit./adam. colourless |
| Wolframite |
(Fe, Mn) WO4 |
7.3 |
4 - 4.5 |
mon., sub-met./adam. greyish-black |
| Chief ore: |
scheelite and wolframite
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| World production: |
45 100 tonnes/year |
| Main mining areas: |
China, Malaysia, Burma, Bolivia, Canada, Australia, Japan, USA |
| Reserves: |
1.5 x 106 tonnes |
| Specimen: |
available as foil, powder, rod or wire. Safe.
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| Abundances |
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| Sun: |
50 (relative to H = 1 x 1012) |
| Earth's crust: |
1 p.p.m. |
| Seawater: |
9.2 x 10-5 p.p.m. |
| Residence time:: |
n.a. |
| Oxidation state: |
VI |
Other sizes and specifications on request
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