Tungsten

TungstenTungsten, or wolfram,[7][8] is a chemical element with symbol W and atomic number 74. The name tungsten comes from the former Swedish name for the tungstate mineral scheelite, from tung sten "heavy stone".[9] Tungsten is a rare metal found naturally on Earth almost exclusively in chemical compounds. It was identified as a new element in 1781, and first isolated as a metal in 1783. Its important ores include wolframite and scheelite. Tungsten,  74W General properties Pronunciation /ˈtʌŋstən/ TUNG-stən Alternative wolfram, pronounced: / name ˈwʊlfrəm/ (WUUL-frəm) Appearance grayish white, lustrous Standard atomic 183.84(1)[1] weight (Ar, standard) Tungsten in the periodic table Mo ↑ W ↓ Sg tantalum ← tungsten → rhenium Atomic number 74 (Z) Group.p.t.) when liquid 17. 8. 2 shell Physical properties Phase (at STP) solid Melting point 3695 K (3422 °C. 18. 6192 °F) Boiling point 6203 K (5930 °C. 32. period 6 Block d-block Element transition metal   category Electron [Xe] 4f14 5d4 6s2[2] configuration Electrons per 2.6 g/cm3 (at m. 10706 °F) Density 19. period group 6. 12.) .25 g/cm3 (near r. −2.27 J/(mol·K) capacity Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 3477 3773 4137 4579 5127 5823 Atomic properties Oxidation states 6. 4. 1.31 kJ/mol[3][4] Heat of 774 kJ/mol vaporization Molar heat 24. 2.36 Ionization 1st: 770 kJ/mol energies 2nd: 1700 kJ/mol Atomic radius empirical: 139 pm Covalent radius 162±7 pm . 0. −4 (a mildly acidic oxide) Electronegativity Pauling scale: 2. 5.Heat of fusion 52. 3. −1. ) (annealed) thin rod Thermal 4.8 nΩ·m (at 20 °C) resistivity Magnetic paramagnetic[5] ordering Magnetic +59. Spectral lines Miscellanea Crystal structure body-centered cubic (bcc) Speed of sound 4620 m/s (at r.t.5 µm/(m·K) (at 25 °C) expansion Thermal 173 W/(m·K) conductivity Electrical 52.0·10−6 cm3/mol (298 K)[6] susceptibility Young's 411 GPa . 28 Mohs hardness 7.modulus Shear modulus 161 GPa Bulk modulus 310 GPa Poisson ratio 0.5 Vickers 3430–4600 MPa hardness Brinell hardness 2000–4000 MPa CAS Number 7440-33-7 History Discovery Carl Wilhelm Scheele (1781) First isolation Juan José Elhuyar and Fausto Elhuyar (1783) Named by Torbern Bergman (1781) Main isotopes of tungsten . and much higher (about 1.43% stable The free element is remarkable for its robustness.7 times) than that of lead. Its density is 19.8×1018 y α 176Hf 181W syn 121. 3695 K).[10] Polycrystalline . Iso‐ Abundance Half-life Decay Pro‐ tope (t1/2) mode duct 180W 0.50% stable 183W 14.2 d ε 181Ta 182W 26.64% stable 185W syn 75. comparable to that of uranium and gold. especially the fact that it has the highest melting point of all the elements discovered.3 times that of water. It also has the second highest boiling point.12% 1. melting at 3422 °C (6192 °F. 6203 K). at 5930 °C (10706 °F.31% stable 184W 30.1 d β− 185Re 186W 28. and radiation shielding.tungsten is an intrinsically brittle[11][12] and hard material (under standard conditions. making it difficult to work. when uncombined). Tungsten . and can be cut with a hard-steel hacksaw. pure single-crystalline tungsten is more ductile.[13] Tungsten's many alloys have numerous applications. X-ray tubes (as both the filament and target). including incandescent light bulb filaments. However. electrodes in TIG welding. superalloys. Tungsten's hardness and high density give it military applications in penetrating projectiles. where it is used in a few species of bacteria and archaea. It is the heaviest element known to be essential to any living organism.[14] Tungsten interferes with molybdenum and copper metabolism and is somewhat toxic to animal life.compounds are also often used as industrial catalysts. Tungsten is the only metal from the third transition series that is known to occur in biomolecules.[15][16] Characteristics Physical properties . [13] It is worked by forging. tungsten has the highest melting point (3422 °C. lowest vapor pressure (at temperatures above 1650 °C.[17] Although carbon remains solid at higher . 6192 °F). tungsten is a hard steel- grey metal that is often brittle and hard to work.In its raw form. If made very pure. tungsten retains its hardness (which exceeds that of many steels). or extruding. Of all metals in pure form. and the highest tensile strength. 3000 °F). and becomes malleable enough that it can be worked easily. drawing. Tungsten objects are also commonly formed by sintering. [10] Tungsten exists in two major crystalline forms: α and β. The former has a body- centered cubic structure and is the more .[18] Alloying small quantities of tungsten with steel greatly increases its toughness.temperatures than tungsten. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons. carbon sublimes at atmospheric pressure instead of melting. so it has no melting point. Tungsten has the lowest coefficient of thermal expansion of any pure metal. mixing the two phases allows obtaining intermediate TC values. 1–4 K. Contrary to the α phase which crystallizes in isometric grains.[22] Such .[20][21] The TC value can also be raised by alloying tungsten with another metal (e.stable form.015 K vs.g. but can coexist with the α phase at ambient conditions owing to non-equilibrium synthesis or stabilization by impurities. it is metastable. the β form exhibits a columnar habit. The structure of the β phase is called A15 cubic. 7. 0.9 K for W-Tc). The α phase has one third of the electrical resistivity[19] and a much lower superconducting transition temperature TC relative to the β phase: ca. 2)×1018 years. this yields about two alpha decays of 180W in one gram of natural tungsten per year.tungsten alloys are sometimes used in low-temperature superconducting circuits.[23][24][25] Isotopes Naturally occurring tungsten consists of five isotopes whose half-lives are so long that they can be considered stable. on average. all five can decay into isotopes of element 72 (hafnium) by alpha emission. but only 180W has been observed[26][27] to do so with a half-life of (1.8 ± 0.[28] . Theoretically. the most stable of which are 181W with a half- life of 121.4 days. 178W with a half-life of 21. 188W with a half-life of 69.The other naturally occurring isotopes have not been observed to decay. constraining their half-lives to be at least 4×1021 years.6 days.[28] All of the remaining radioactive isotopes have half-lives of less than 3 hours. and 187W with a half-life of 23. 185W with a half-life of 75.1 days. and most of these have half-lives below 8 minutes.2 days. Another 30 artificial radioisotopes of tungsten have been characterized.72 h.[28] Tungsten also has . . Chemical properties Elemental tungsten resists attack by oxygen.[29][30] Tungsten typically combines with oxygen to form the yellow tungstic oxide. but it exhibits all oxidation states from −2 to +6. the most stable being 179mW (t1/2 6.[29] The most common formal oxidation state of tungsten is +6.4 meta states.4 minutes). WO3. WO2− 4 . and alkalis. which dissolves in aqueous alkaline solutions to form tungstate ions. acids. H2W12O 10– [31] 42 . it first yields the soluble. W2C is resistant to chemical attack. As tungstate is progressively treated with acid. Further acidification produces the . metastable "paratungstate A" anion.Tungsten carbides (W2C and WC) are produced by heating powdered tungsten with carbon. tungstate gives the heteropoly acids and polyoxometalate anions under neutral and acidic conditions.[10] In aqueous solution. which over time converts to the less soluble "paratungstate B" anion. although it reacts strongly with chlorine to form tungsten hexachloride (WCl6). W7O 6– 24 . The inclusion of a different atom such as phosphorus in place of the two central hydrogens in metatungstate produces a wide variety of heteropoly acids. such as phosphotungstic acid H3PW12O40. H2W12O 6– 40 . Many other polyoxometalate anions exist as metastable species. after which equilibrium is reached. These are .very soluble metatungstate anion. The metatungstate ion exists as a symmetric cluster of twelve tungsten-oxygen octahedra known as the Keggin anion. Tungsten trioxide can form intercalation compounds with alkali metals. Carl Wilhelm Scheele discovered that a new acid. at the Royal Basque Society in the town of Bergara.[32] Scheele and Torbern Bergman suggested that it might be possible to obtain a new metal by reducing this acid.[33] In 1783. History In 1781.known as bronzes. could be made from scheelite (at the time named tungsten). the . Later that year. Spain. José and Fausto Elhuyar found an acid made from wolframite that was identical to tungstic acid. an example is sodium tungsten bronze. tungstic acid. its hardness and density. and its strengthening of alloys made it an important raw material for the arms . was put under pressure from both sides. Portugal. and they are credited with the discovery of the element. because of its deposits of wolframite ore at Panasqueira.brothers succeeded in isolating tungsten by reduction of this acid with charcoal. as the main European source of the element.[34][35][36] In World War II. tungsten played a significant role in background political dealings. Tungsten's desirable properties such as resistance to high temperatures. but not in the Nordic countries. French. Tungsten was the old Swedish name for the mineral scheelite. "Wolfram" (or "volfram") is used in most European (especially Germanic and Slavic) languages.[37][38] both as a constituent of weapons and equipment and employed in production itself.g. in tungsten carbide cutting tools for machining steel. Etymology The name "tungsten" (from the Swedish tung sten.industry. "heavy stone") is used in English. and many other languages as the name of the element.. e. and is derived from the mineral . which translates into English as "wolf's froth". the name given to tungsten by Johan Gottschalk Wallerius in 1747.[39] Occurrence .[13] The name "wolframite" is derived from German "wolf rahm" ("wolf soot" or "wolf cream"). This. which is the origin of the chemical symbol W. and is a reference to the large amounts of tin consumed by the mineral during its extraction. the name Georg Agricola used for the element in 1546. in turn.wolframite. derives from "lupi spuma". and have almost no economical value. with a scale in cm.Wolframite mineral. and hübnerite MnWO4) and scheelite (calcium tungstate (CaWO4). Tungsten is found mainly in the mineral wolframite (iron–manganese tungstate (Fe. . which is a solid solution of the two minerals ferberite FeWO4.Mn)WO4. Other tungsten minerals range in their level of abundance from moderate to very rare. 300 tonnes of tungsten concentrates were produced in the year 2009.000 tonnes.Production Tungsten mined in 2012 About 61.[41] The main producers were as follows (data in tonnes):[42] .[40] and in 2010. world production of tungsten was about 68. 966 2.964 420 1.023 1.194  Bolivia 1.050  Portugal 823 799 819 763  Austria 887 977 861 706  Rwanda 380 330 520 700  Spain 225 240 497 542  Brazil 192 166 244 381  Australia 33 18 15 290  Peru 502 571 439 276  Burundi 110 100 165 190  Myanmar 874 163 140 140  North Korea 100 110 110 100  Congo 200 25 70 95  Thailand 190 300 160 80  Mongolia 39 20 13 66  Uganda 7 44 8 21 Total 61.150 1.665 2.537  Canada 1.400 .000 59.204 1.900 76.400 73.200 68.Major producers of tungsten[41] Production (tonnes) Country 2009 2010 2011 2012  China 51.635 1.124 1.000 61.314 3.785 3.247  Vietnam 725 1.000  Russia 2.800 64. Tungsten mining in Rwanda forms an important part of the country's economy. There is additional production in the U.S., but the amount is proprietary company information. U.S. reserves are 140,000 tonnes.[42] US industrial use of wolfram is 20,000 tones: 15,000 tones are imported and the remaining 5,000 tones come from domestic recycling.[43] Tungsten is considered to be a conflict mineral due to the unethical mining practices observed in the Democratic Republic of the Congo.[44][45] There is a large deposit of tungsten ore on the edge of Dartmoor in the United Kingdom, which was exploited during World War I and World War II as the Hemerdon Mine. With recent increases in tungsten prices, as of 2014 this mine has been reactivated.[46] Tungsten is extracted from its ores in several stages. The ore is eventually converted to tungsten(VI) oxide (WO3), which is heated with hydrogen or carbon to produce powdered tungsten.[33] Because of tungsten's high melting point, it is not commercially feasible to cast tungsten ingots. Instead, powdered tungsten is mixed with small amounts of powdered nickel or other metals, and sintered. During the sintering process, the nickel diffuses into the tungsten, producing an alloy. Tungsten can also be extracted by hydrogen reduction of WF6: WF6 + 3 H2 → W + 6 HF or pyrolytic decomposition:[47] If converted to the metal equivalent. they were about US$19 per kilogram in 2009. WF6 → W + 3 F2 (ΔHr = +) Tungsten is not traded as a futures contract and cannot be tracked on exchanges like the London Metal Exchange. The prices are usually quoted for tungsten concentrate or WO3.[40] Applications Close-up of a tungsten filament inside a halogen lamp . Close up of a tungsten filament inside a halogen lamp Tungsten carbide ring (jewelry) 1 kilogram tungsten cylinder (scale shown below) Approximately half of the tungsten is consumed for the production of hard . and "carbide" cutting tools such as knives. milling and turning tools used by the metalworking. WC is an efficient electrical conductor. but W2C is less so. with a melting point of 2770 °C. .materials – namely tungsten carbide – with the remaining major use being in alloys and steels. circular saws. one of the hardest carbides.[48] Hard materials Tungsten is mainly used in the production of hard materials based on tungsten carbide. Less than 10% is used in other chemical compounds. WC is used to make wear-resistant abrasives. drills. This type of industrial use accounts for about 60% of current tungsten consumption.[10] Carbide tooling is actually a ceramic/metal composite. where metallic cobalt acts as a binding (matrix) material to hold the WC particles in place.[49] The jewelry industry makes rings of sintered tungsten carbide. tungsten carbide/metal composites. petroleum and construction industries. Sometimes .[50] WC/metal composite rings use nickel as the metal matrix in place of cobalt because it takes a higher luster when polished.woodworking. mining. and also metallic tungsten. [51] Because of tungsten carbide's hardness. and may crack under a sharp blow. A good example is high speed steel. but it is a ceramic. rings made of this material are extremely abrasion resistant. which can contain as much as 18% tungsten.[53] .manufacturers or retailers refer to tungsten carbide as a metal. however.[52] Alloys The hardness and density of tungsten are applied in obtaining heavy metal alloys. and will hold a burnished finish longer than rings made of metallic tungsten. Tungsten carbide rings are brittle. are used in turbine blades and wear- resistant parts and coatings. Quenched (martensitic) tungsten steel (approx.[54] Tungsten alloys are used in a wide range of different applications.5% to 7. 5.0% W with 0. as .7% C) was used for making hard permanent magnets.5% to 0. such as Hastelloy and Stellite. due to its high remanence and coercivity.Tungsten's high melting point makes tungsten a good material for applications like rocket nozzles. including the aerospace and automotive industries and radiation shielding.[55] Superalloys containing tungsten. for example in the UGM-27 Polaris submarine-launched ballistic missile. when present in steel in these proportions. while the element tungsten is not ferromagnetic (but iron is). it stabilizes the martensite phase.1898) as early as 1886. as compared to the ferrite (iron) phase. Tungsten's heat resistance makes it useful in arc welding applications when combined with another highly-conductive .noted by John Hopkinson (1849 . For example. which has an enhanced ferromagnetism. The magnetic properties of a metal or an alloy are very sensitive to microstructure. due to its greater resistance to magnetic domain wall motion. metal such as silver or copper. in applications where uranium's radioactivity is problematic even in depleted form. or where uranium's additional pyrophoric . usually alloyed with nickel and iron or cobalt to form heavy alloys. is used in kinetic energy penetrators as an alternative to depleted uranium. The silver or copper provides the necessary conductivity and the tungsten allows the welding rod to withstand the high- temperatures of the arc welding environment. Armaments Tungsten. Germany used tungsten during World War II to produce shells for anti-tank gun designs using the Gerlich "squeeze" principle to achieve very high muzzle velocity and enhanced armor penetration from comparatively small caliber and light weight field artillery. . tungsten alloys have also been used in cannon shells. in ordinary small arms bullets designed to penetrate body armor). The weapons were highly effective but a shortage of tungsten used in the shell core limited that effectiveness.properties are not required (for example. to create supersonic shrapnel. Similarly. grenades and missiles. [57] MoS2 is more commonly used for such applications.[58] Tungsten oxides are used in ceramic glazes and calcium/magnesium tungstates are used widely in fluorescent .[56] Chemical applications Tungsten(IV) sulfide is a high temperature lubricant and is a component of catalysts for hydrodesulfurization. which use it as dense powder to reduce collateral damage while increasing the lethality of explosives within a small radius.Tungsten has also been used in Dense Inert Metal Explosives. lighting. Other salts that contain tungsten are used in the chemical and tanning industries.[17] Tungsten trioxide powder Tungsten oxide (WO3) is incorporated into selective catalytic reduction (SCR) catalysts found in coal-fired power plants. Crystal tungstates are used as scintillation detectors in nuclear physics and nuclear medicine. These catalysts convert nitrogen oxides . counterweights.(NOx) to nitrogen (N2) and water (H2O) using ammonia (NH3). depleted uranium is also used for these purposes. ballast keels for yachts. tail ballast for commercial aircraft. due to similarly high density. Seventy-five-kg blocks of tungsten were used as "cruise balance mass devices" on . The tungsten oxide helps with the physical strength of the catalyst and extends catalyst life.[59] Niche uses Applications requiring its high density include weights. and as ballast in race cars for NASCAR and Formula One. High-density alloys of tungsten with nickel. It is an ideal material to use as a dolly for riveting.[61] Tungsten is used as an absorber on the . copper or iron are used in high-quality darts[60] (to allow for a smaller diameter and thus tighter groupings) or for fishing lures (tungsten beads allow the fly to sink rapidly).the entry vehicle portion of the 2012 Mars Science Laboratory spacecraft. The extra density gives this string more projection and often cellists will buy just this string and use it with three strings from a different set. where the mass necessary for good results can be achieved in a compact bar. Some cello C strings are wound with tungsten. Gold substitution Its density.electron telescope on the Cosmic Ray System of the two Voyager spacecraft.[13][63] Metallic tungsten is hypoallergenic. making it useful . a mixture of different chemicals used in the "Lowry Assay" for protein content analysis. and is harder than gold alloys (though not as hard as tungsten carbide).[62] Sodium tungstate is used in Folin- Ciocalteu's reagent. allows tungsten to be used in jewelry as an alternative to gold or platinum. similar to that of gold. especially in designs with a brushed finish.[64] . Because the density is so similar to that of gold (tungsten is only 0. and replacing the removed gold with tungsten rods. such as by plating a tungsten bar with gold. tungsten can also be used in counterfeiting of gold bars.36% less dense).[64][65][66] which has been observed since the 1980s.[67] or taking an existing gold bar.[68] The densities are not exactly the same. but gold-plated tungsten will pass superficial tests. and other properties of gold and tungsten differ.for rings that will resist scratching. drilling holes. both in jewelry and as bars. elemental tungsten is used in many high- temperature applications. and vacuum tube filaments.[70] such as light bulb. heating elements. cathode-ray tube.[69] Electronics Because it retains its strength at high temperatures and has a high melting point. and rocket engine nozzles.[13] Its high melting point also makes tungsten suitable for aerospace and high-temperature uses .Gold-plated tungsten is available commercially from China (the main source of tungsten). such as electrical, heating, and welding applications, notably in the gas tungsten arc welding process (also called tungsten inert gas (TIG) welding). Tungsten electrode used in a Gas tungsten arc welding torch Because of its conductive properties and relative chemical inertness, tungsten is also used in electrodes, and in the emitter tips in electron-beam instruments that use field emission guns, such as electron microscopes. In electronics, tungsten is used as an interconnect material in integrated circuits, between the silicon dioxide dielectric material and the transistors. It is used in metallic films, which replace the wiring used in conventional electronics with a coat of tungsten (or molybdenum) on silicon.[47] The electronic structure of tungsten makes it one of the main sources for X-ray targets,[71][72] and also for shielding from high-energy radiations (such as in the radiopharmaceutical industry for shielding radioactive samples of FDG). It is also used in gamma imaging as a material from which coded apertures are made, due to its excellent shielding properties. Tungsten powder is used as a filler material in plastic composites, which are used as a nontoxic substitute for lead in bullets, shot, and radiation shields. Since this element's thermal expansion is similar to borosilicate glass, it is used for making glass-to-metal seals.[17] In addition to its high melting point, when tungsten is doped with potassium, it leads to an increased shape stability (compared to non-doped tungsten). This ensures that the filament does not sag, and no undesired changes occur.[73] tungsten nanowires have been fabricated and studied since 2002. the mechanical properties differ fundamentally from those of bulk tungsten.[76] In similarity to silicon nanowires.[75] Such tungsten nanowires have potential applications in nanoelectronics and importantly as pH probes and gas sensors. tungsten nanowires are frequently produced from a bulk tungsten .[74] Due to a particularly high surface to volume ratio.Nanowires Through top-down nanofabrication processes. the formation of a surface oxide layer and the single crystal nature of such material. [77] Using the Deal– Grove model it is possible to predict the oxidation kinetics of nanowires fabricated through such thermal oxidation processing.precursor followed by a thermal oxidation step to control morphology in terms of length and aspect ratio. is the heaviest element known to be biologically functional. enzymes called oxidoreductases . but not in eukaryotes.[78] Biological role Tungsten. It is used by some bacteria and archaea[79]. at atomic number 74. with the next heaviest being iodine (Z = 53). For example. and in this case the tungsten-selenium pair may function analogously to the molybdenum-sulfur pairing of some molybdenum cofactor- requiring enzymes. despite its name. Tungsten-using enzymes typically reduce carboxylic acids to aldehydes. does not contain molybdenum. The first tungsten- requiring enzyme to be discovered also requires selenium.[80] The tungsten oxidoreductases may also catalyse oxidations.[81] One of the enzymes . but may complex with either molybdenum or tungsten in use by living organisms).use tungsten similarly to molybdenum by using it in a tungsten-pterin complex with molybdopterin (molybdopterin. a tungsten- .[83] Although a tungsten- containing xanthine dehydrogenase from bacteria has been found to contain tungsten-molydopterin and also non- protein bound selenium.[82] Acetylene hydratase is an unusual metalloenzyme in that it catalyzes a hydration reaction. Two reaction mechanisms have been proposed. in one of which there is a direct interaction between the tungsten atom and the C≡C triple bond.in the oxidoreductase family which sometimes employ tungsten (bacterial formate dehydrogenase H) is known to use a selenium-molybdenum version of molybdopterin. It can be selectively or non-selectively imported by some prokaryotic organisms and may substitute for molybdate in certain enzymes.selenium molybdopterin complex has not been definitively described.[84] In soil. Its effect on the action of these enzymes is in some cases inhibitory and in others positive. alkaline soils cause monomeric tungstates. acidic soils cause polymeric tungstates.[86] .[85] The soil's chemistry determines how the tungsten polymerizes. tungsten metal oxidizes to the tungstate anion. [87] Tungsten has been studied as a biological copper metabolic antagonist. in a role similar to the action of molybdenum.[88] In archaea . but the tungstate completely inhibited their reproductive ability. similar to the tetrathiomolybdates. It has been found that tetrathiotungstates may be used as biological copper chelation chemicals.Sodium tungstate and lead have been studied for their effect on earthworms. Lead was found to be lethal at low levels and sodium tungstate was much less toxic. The following tungsten-utilizing enzymes are known: Aldehyde ferredoxin oxidoreductase (AOR) in Thermococcus strain ES-1 Formaldehyde ferredoxin oxidoreductase (FOR) in Thermococcus litoralis Glyceraldehyde-3-phosphate ferredoxin oxidoreductase (GAPOR) in Pyrococcus furiosus A wtp system is known to selectively transport tungsten in archaea: .Tungsten is essential for some archaea. the effects of tungsten on the environment are limited.[90] It was first believed to be relatively inert and an only slightly toxic metal. beginning in the year 2000. WtpA is tungten-binding protein of ABC family of transporters WptB is a permease WtpC is ATPase[89] Health factors Because tungsten is rare and its compounds are generally inert. the risk exerted by tungsten alloys. its dusts and particulates to induce cancer and several other adverse effects in animals as well as humans has been highlighted from in vitro . skin contact. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 5 mg/m3 over an 8-hour workday and a short term limit of 10 mg/m3.[95][96] People can be exposed to tungsten in the workplace by breathing it in.[97] . and eye contact. [91][92] The median lethal dose LD50 depends strongly on the animal and the method of administration and varies between 59 mg/kg (intravenous. swallowing it. rats). intraperitoneal. rabbits)[93][94] and 5000 mg/kg (tungsten metal powder.and in vivo experiments. overturning U. Patent 1.933 granted in 1913 to William D.Patent claim Tungsten is unique amongst the elements in that it has been the subject of patent proceedings. a US court rejected General Electric's attempt to patent it. In 1928.082. Coolidge.S.[98][99] See also Field emission gun Tungsten oxide List of chemical elements name etymologies . Pure and Applied Chemistry. Bluffton College. Dan. Lide. 2.. List of chemical elements naming controversies References 1. J.). Boca Raton. Berger. ed. doi:10. p. "Why does Tungsten not 'Kick' up an electron from the s sublevel ?" .1515/pac-2015-0305 . USA. (2016). (2009). et al. "Atomic weights of the elements 2013 (IUPAC Technical Report)" . 6-134. David R. Florida: CRC Press. CRC Handbook of Chemistry and Physics (90th ed.. ISBN 978-1-4200-9084-0. . Meija. 3. 88 (3): 265–91. R. Boca Raton (FL): CRC Press. Florida: Chemical Rubber Company Publishing. (2017). 8. wolfram on Merriam-Webster. Lide. (2005). pp.). . ISBN 0-8493-0464-4. 6. wolfram on Oxford Dictionaries. ed. Tolias P.. 7.06302  . 5.4. E110. D. ISBN 0-8493-0486-5. "Analytical expressions for thermophysical properties of solid and liquid tungsten relevant for fusion applications". arXiv:1703. "Magnetic susceptibility of the elements and inorganic compounds". CRC Handbook of Chemistry and Physics (PDF) (86th ed. Handbook of Chemistry and Physics. Boca Raton. Weast. Robert (1984). CRC. T. Oxford University Press. technology of the element. 12. Daintith. Springer. and chemical compounds . John (2005). September 2005. "low temperature brittleness".. Wolf-Dieter (1999). Wurster.). Erik. B.). 11.) 10. .9. ISBN 0-8160-5649-8. (2011). Oxford English Dictionary (3rd ed. S. Weingärtner. Facts on File Dictionary of Chemistry (4th ed.. Pippan. Gludovatz. pp. ISBN 978-0-306-45053-2. chemistry. "Tungsten" . Lassner. New York: Checkmark Books. Tungsten: properties. alloys. Schubert. R. A.. 20–21.. (Subscription or UK public library membership required. Hoffmann. Philosophical Magazine. L.91. A Guide to the elements (2nd ed. Tuorto.3006G .2011."Influence of impurities on the fracture behavior of tungsten"... E.. M. Long. McGuinness. Lopez- Chiaffarelli. 10 (4): . Stwertka. Häggblom..1080/14786435. R. Williams. Bibcode:2011PMag. Kerkhof.).. S.. PLoS ONE.. CO Field Research Site" . J. N. (2015). Albert (2002). 14. M.558861 . K. 13. H. ISBN 0-19-515026-0. "Spatial Distribution of an Uranium-Respiring Betaproteobacterium at the Rifle. 91 (22): 3006–3020.. L. doi:10.. J. M. New York: Oxford University Press. Koribanics. P. N. PMC 4395306  . 2 (2): 201– 207. 27 (7): 360–367. PMID 12114025 . Trends in Biochemical Sciences. doi:10. doi:10. Hille. . Russ (2002). J.0123378 . doi:10. "The active sites of molybdenum- and tungsten-containing enzymes".1016/S0968-0004(02)02107-2 . 15. John H (1998). PMID 25874721 . McMaster. 16.e0123378. "Molybdenum and tungsten in biology". PMID 9667924 .pone.1371/journal. & Enemark. Current Opinion in Chemical Biology.1016/S1367-5931(98)80061-6 . "Tuning of Tungsten Thin Film . L. Tungsten: properties.. and chemical compounds . technology of the element. C.). (2004). chemistry. Balzar. A. Hammond. E. Heather Bean Material Properties and Analysis Techniques for Tungsten Thin Films Archived 2011-10-23 at the Wayback Machine. CRC press. p. R. 9. The Elements. Lita. ISBN 0-8493-0485-7. Rosenberg. ISBN 0-306-45053-4. R. Lassner. Nam.. D. S. E. in Handbook of Chemistry and Physics (81st ed.. Wolf-Dieter (1999). Schwall. Schubert. Kaatz. D.17.. Erik. Springer... A. 1998 20. 18. October 19. alloys.. 19. M. (2005). Miller. 849033 . E. S. Hulm. C.. Suso Gygax (1966). 15 (2): 3528–3531. H.101 . R. 22.1109/TASC. S. R.Superconducting Transition Temperature for Fabrication of Photon Number Resolving Detectors" (PDF). "Superconductivity of Tungsten".16. Vilches.1103/PhysRevLett. "Superconducting Technetium- .101J .2005. Johnson. 21. Wheatley.. K. IEEE Transactions on Applied Superconductivity. doi:10. J. J. T. Autler.. Archived (PDF) from the original on 2013-05-13. doi:10. Kemper (1965). Physical Review Letters..16. O. 16 (3): 101–104. Bibcode:1966PhRvL. H Bouchiat (2007). Yu. R Deblock. Bibcode:2007EL.. Tsukagoshi.1177A . 140 (4A): A1177–A1180. Y. Kodama. Physical Review. T. M. A Kasumov.. W Nativel.. I. 24. Kasumov..140. Shailos. doi:10. C Collet. Nishikawa. A. Ikemoto. . Senba.7957008S .1209/0295-5075/79/57008 . K. Aoyagi. "Proximity effect and multiple Andreev reflections in few-layer graphene".140.Tungsten Alloys".. A. T.1103/PhysRev. K. Europhysics Letters (EPL). arXiv:cond-mat/0612058  . H. Kobayashi. Kawamura. 79 (5): 57008.A1177 .. M Ferrier.. S Guéron. Bibcode:1965PhRv. doi:10. 23. 033414 . T. K. Sun. D. Bibcode:1987PhRvB. M. doi:10. M. P. Quate (1987). F. M. Physical Review B. J. S. Kasumov. B.. Smith. Bouchiat (2005).72c3414K .K. D. A. . T. Hahn. Oh. Geballe. Kirk. 35 (16): 8850–8852. Naito.8850K . C. H. H. 72 (3): 033414. R.. J. M. Webb. R. Kikuchi. D. Z. R. B. Bibcode:2005PhRvB. Deblock. arXiv:cond-mat/0402312  . Kapitulnik. Char. A. 25. Hammond. "Proximity effect in a superconductor- metallofullerene-superconductor molecular junction". V..1103/PhysRevB.35. Yu. D. "Point-contact electron tunneling into the high-T_{c} superconductor Y-Ba-Cu- O". R. Beasley. Guéron. E. H.72. Volkov. Mitzi. Physical Review B. (2004). Phys. et al. arXiv:nucl-ex/0211013  . (2003).67. "Detection of the natural α decay of tungsten". 67 (1): 014310. Rev.. 28. Rev. "Interactive Chart of Nuclides" . doi:10. Archived from the original on 2008-05-22.1103/PhysRevC.70.. . et al.1103/PhysRevC.35. National Nuclear Data Center: Brookhaven National Laboratory. Cozzini. doi:10. "α activity of natural tungsten isotopes". 70 (6): 064606. 26. Bibcode:2004PhRvC.064606 .67a4310D . arXiv:nucl-ex/0408006  ..doi:10. Bibcode:2003PhRvC. Danevich.8850 . F.014310 . C. Sonzogni.1103/PhysRevB. 27. Alejandro. C. A. Phys. C.70f4606C .. (2008). John E. M. G. Smith.).. (2000). 30. Emsley. P. D.. Kim. "Ethylene Complexes of the Early Transition Metals: Crystal Structures of [HfEt4(C2H4)2−] and the Negative-Oxidation-State Species [TaHEt(C2H4)33−] and [WH(C2H4)43−]". (1991). Patrick. Morse. "Quantitative Determination of Sodium Metatungstate Speciation by 183W . 31. doi:10. ISBN 0-19-855569-5. 29. S. Vincent A.1021/om701189e . Organometallics.. 27 (5): 984–993. Bradley J. Girolami. D.Retrieved 2008-06-06. Q.. Y. New York: Oxford University Press. Shelby. The elements (2nd ed. 53 (12): 965. doi:10. See: Scheele. Kungliga Vetenskaps Academiens Nya Handlingar (Royal Scientific Academy's New Proceedings). Carl Wilhelm (1781) "Tungstens bestånds-delar" (Tungsten's constituents). Australian Journal of Chemistry. 2 : 89–95. CSIRO. 4–13 of: de Luyart.1071/CH00140 . 32. (in Swedish) English translation on pp.M. with .N. Retrieved 2008-06-17. Spectroscopy" . John Joseph and Fausto. Archived from the original on 2008-04-03.R. 35. "ITIA Newsletter" (PDF). 1785). June 2005. 34. Charles Cullen. Saunders. Archived from the original on July 21. Chicago. "ITIA Newsletter" (PDF). England. Nicol. Illinois: Heinemann Library. December . trans. International Tungsten Industry Association. Which Enters its Composition (London. A Chemical Analysis of Wolfram and Examination of a New Metal. Tungsten and the Elements of Groups 3 to 7 (The Periodic Table). ISBN 1-4034-3518-9. 33. Retrieved 2008-06-18.. International Tungsten Industry Association. G. Nigel (2004). 2011. 36. See: de Luyart. and examination of a new metal. Archived from the original on July 21. . and F. Extractos de las Juntas Generales celebradas por la Real Sociedad Bascongada de los Amigos del País en la ciudad de Vitoria por setiembre de 1783. J. 2011. pp. which enters into its composition).2005. y examen de un nuevo metal. 46–88. que entra en su composición" (Chemical analysis of wolframite. (September 1783) "Análisis químico del volfram.J. Retrieved 2008-06-18. with Charles Cullen. and Stone Daley. Rebecca W. A Chemical Analysis of Wolfram and Examination of a New Metal. Which Enters its Composition (London. (1999) "The Delhuyar brothers. Nicol. "World War II Economic Warfare: The United States. (1999). . de Luyart. 23 : 11–19. John Joseph and Fausto. tungsten.. Stevens. Available at: University of Illinois (USA) Archived 2015-12-30 at the Wayback Machine. 1785). Caswell. and Spanish silver. England. 37. trans. Lyman R. Donald G." Bulletin for the History of Chemistry. G. van der Krogt. Kim B. "The Price of Neutrality: Portugal. and Portuguese Wolfram" . (2009). Archived from the original on 2011-06-28. 38. Archived from the original on 2010-01-23. JSTOR 3513391 . Shedd. United States Geological Survey. Questia. Douglas (Summer 1986). Luso- Brazilian Review. The Historian. "Tungsten (table 15)" (PDF). "Wolframium Wolfram Tungsten" . Retrieved 2010-03-11. L. 40. Archived (PDF) from the original on . the Wolfram Question. 23 (1). Elementymology & Elements Multidict. Peter. and World War II".Britain. 39. Wheeler. 2016. Archived from the original on December 4. Mineral Commodity Summaries. 42. U. Nicholas D. "The Trouble With Tungsten" . resourceinvestor. By Country" . The New York Times. Geological Survey. 44. 43. 176–177 Archived 2011-10-28 at the Wayback Machine. Retrieved 2015-08-30. (2010-06-27). "Tungsten: World Concentrate Production. IndexMundi.2011-10-28. Kristof. Retrieved 2011-06-18.com. 2006. Archived from the original on 2015-09-24. February 1. January 2011 pp.S. . "Death by Gadget" . 41. 2014-09-03. 48. 45.Archived from the original on 2016-08-31.. July 16. Tungsten Alloys. 9 June 2014 47. BBC News. Eberhard Lüderitz. McGraw-Hill. Schey. "Work starts on £130m Devon tungsten mine" Archived 2014-12-05 at the Wayback Machine.. John A.). Hans Uwe Wolf. 2010 46. and Tungsten . The Daily Beast. Introduction to Manufacturing Processes (2nd ed. Erik Lassner. "Tungsten. The Genocide Behind Your Smart Phone Archived 2011-11-17 at the Wayback Machine. (1987). Wolf-Dieter Schubert. Inc. Don Law-West. Blair. History. 35–.a27_229 . Tungsten: The Element. (2012) 51. . The Canadian Encyclopaedia. Bamberg. Globe Pequot. Wiley-VCH. ISBN 978-1-59921-397-2. Kim (2009). Archived from the original on 2014-09-29. 49.1002/14356007. Retrieved 2009-05-05. Weber. Uses and Wedding Bands Archived 2013-09-21 at the Wayback Machine. pp. Christy. Louis Perron. de Laubenfels. Knack Planning Your Wedding: A Step-by-Step Guide to Creating Your Perfect Day .Compounds" in Ullmann's Encyclopedia of Industrial Chemistry.. "Tungsten" . Weinheim. 50. doi:10. Ramakrishnan. ISBN 978-0-470-44431-3. New Age International. "Powder metallurgy for Aerospace Applications". 138–. electrical/electronic and engineering industry . 2000–2008. John Wiley and Sons. Archived from the original on 2008-08-15. . (2007). pp. Azom. Ken (2009). 53. ISBN 81-224-2030-3. Archived from the original on 2014-09-30.52. 54. Retrieved 2008-06-18. Schultz. Ken Schultz's Essentials of Fishing: The Only Guide You Need to Catch Freshwater and Saltwater Fish . Powder metallurgy: processing for automotive. "Tungsten Applications – Steel" . P. 38. p. Tungsten Applications Archived 2013- 09-01 at the Wayback Machine. 57. ISBN 978- 0-444-50214-8. 7th European workshop. Dense Inert Metal Explosive (DIME) Archived 2008-08-28 at the Wayback Machine.. 1999 . Belgium. Retrieved on 2011-08-07. Archived from the original on 30 May 2013.com 56. (1999). November 14–17.55. Gilbert F. Antwerpen. 351–. Elsevier. Bernard & Froment. pp. Retrieved 18 December . wolfmet.com.. Delmon. Hydrotreatment and hydrocracking of oil fractions: proceedings of the 2nd international symposium. Defense-update. Mang. Kerry (2004). Catalysis . Retrieved 18 December 2011. Marshall Cavendish. 60. Lubricants and Lubrication . 24. ISBN 978-3-527- 61033-4. Archived from the original on 30 May 2013. Retrieved 18 December 2011. Royal Society of Chemistry. Theo & Dresel. . ISBN 978-0-85404-224-1. Wilfried (28 May 2007). pp. 59. pp. Turrell. John Wiley & Sons. Spivey. 239–. Archived from the original on 30 May 2013. Tungsten .2011. 58. p. ISBN 0-7614- 1548-3. (2002). 695–. James J.  190–192. Popular Science. "Why Spirocore Tungsten C String" . Theo (March 14.61. . "CRS Instruments" .com. "tungsten". 62. Archived from the original on 2017-02-01. 64. Westport. (2007). cello-strings. 2008). Hesse. 63. Jewelrymaking through history: an encyclopedia . "How to Make Convincing Fake-Gold Bars" . Archived from the original on January 25. ISBN 978- 0-313-33507-5. Rayner W. Gray. 2015. Archived from the original on 2016-05-10.: Greenwood Press. Retrieved 2008-06-18. Conn. pp. NASA. Archived from the original on 2012-03-27. Heller. Reuters (1983-12-22).". Retrieved 2012-03-25. Patrick A. March 2. Tungsten Gold & Lost Respect Archived 2011-10-08 at the Wayback Machine. Largest Private Refinery Discovers Gold-Plated Tungsten Bar Archived 2012- 03-23 at the Wayback Machine. reporting story by ProSieben 67. Nov 18 2009 66.65. Jim Willie. "Austrians Seize False Gold Tied to London Bullion Theft" .. . 2010. "Zinc Dimes. The New York Times. Tungsten Alloy for Gold Substitution Archived 2012-03-22 at the Wayback Machine. 71. Murry. Christensen. ABC Bullion. 2012 69. Curry. Tungsten filled Gold bars Archived 2012-03-26 at the Wayback Machine.. New York: MacMillan Publishing. (1990-08-01). DeGarmo.).. Christensen's physics of diagnostic radiology . Dowdey. China Tungsten 70.. March 22. Thomas S.. 29–35.. James E. Edward E. Thursday. Materials and Processes in Manufacturing (5th ed.68. Archived from the original on 2017-11-11. Paul (1979). pp. ISBN 978- 0-8121-1310-5. . E. Robert C. (2016). Patent 6. 74.S.. M.Union City Filament" . 75. J of Materials Chemistry. "Non-Sag Doped Tungsten .428. "Two- dimensional modeling of the self-limiting . J. Union City Filament. Volker Cimalla (2008). Wayne Charles et al. 77. Liu. "Nanomechanics of single crystalline tungsten nanowires" . CNR Rao (2006). (August 6.904 73. "From Surfactant–Inorganic Mesostructures to Tungsten Nanowires". "High-sensitivity hydrocarbon sensors based on tungsten oxide nanowires". Hasz. et al. Li Yadong.. Retrieved 2017-04-28. Peng. Journal of Nanomaterials. 76.72. 2002) "X-ray target" U. Archived (PDF) from the original on 2017-03-15. "Thermal oxidation of polycrystalline tungsten nanowire" (PDF). JTL Thong (2010). . (5 March 1993). 79. Theoretical and Applied Mechanics Letters. doi:10.taml.oxidation in silicon and tungsten nanowires" . Mukund S. Journal of Biological Chemistry.1016/j.08.002 . Johnson JL1. 268 (7): 4848–52.2016. 6 (5): 195–199. Adams MW. Rajagopalan KV. 78. "Identification of molybdopterin as the organic component of the tungsten cofactor in four enzymes from hyperthermophilic Archaea". Journal of Applied Physics. 81. (1998). Stiefel. Springer. "Transition metal sulfur chemistry and its relevance to molybdenum and tungsten enzymes" (PDF). 80. Pure Appl. V.. I. 70 (4): 889–896. ISBN 0-306-45053- 4. Erik (1999). Archived (PDF) from the original on 2008-12-03. pp. Technology of the Element. Alloys and Chemical Compounds . S. E.1351/pac199870040889 .PMID 8444863 . "Selenium-Containing Formate Dehydrogenase H from Escherichia coli: A . Tungsten: Properties. 82. (1998). Lassner. 409–411. Chemistry. doi:10. Chem. Khangulov. et al. Living on acetylene. 37 (10): 3518– 3528. 84. "Selenium- . "Chapter 2.1007/978-94-017-9269-1_2 . PMID 9521673 . Martha E. The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Sosa Torres. doi:10. (1999). 14. pp. ten Brink. doi:10. Biochemistry. A Primordial Energy Source". Springer. Kroneck. 83.H. Metal Ions in Life Sciences. In Peter M. Schrader. Jan R. Thomas. Felix (2014).Molybdopterin Enzyme That Catalyzes Formate Oxidation without Oxygen Transfer". Annette.1021/bi972177k . Andreesen. 15–35. Rienhofer. Chemical & Engineering News.1046/j. J. "Tungsten. 85. Rachel A. Petkewich.1432- 1327. (2008).00678. the Surprisingly Positively Acting Heavy Metal Element for Prokaryotes".. PMID 10491134 . (19 January 2009).1419. Andreesen.003 . Eur. 264 (3): 862–71. 1125: 215–229. PMID 18096847 . 86. doi:10.1196/annals. Annals of the New York Academy of Sciences. J. doi:10.. Biochem.1999.x . Makdessi. .215A . R. Bibcode:2008NYASA1125. 87 (3): 63–65. "Unease over Tungsten" . K.containing xanthine dehydrogenase from Eubacterium barkeri". "Thiotungstate-copper interactions II. doi:10. .1021/cen-v087n003. The effects of tetrathiotungstate on systemic copper metabolism in normal and copper-treated rats". growth. doi:10. Inouye. (2006). S. 88. et al.1016/0162-0134(94)80005- 7. ISSN 0009-2347 . Lamand M. eisenia fetida".p063 . 87. 25 (3): 763. McQuaid A.1 .1897/04- 578R. 53 (3): 205. "Tungsten effects on survival. Mason J (1994). and reproduction in the earthworm. L. Environmental Toxicology & Chemistry.doi:10.. J Inorg Biochem. Zoroddu. Caister Academic Press. Arienti. ISBN 978- 1904455271. Vaughan. Dermatas. A. Brocato. S.2005.chemosphere.. Cartularo. (2015). (1 April 2008). ed. A. Strigul. Sun. F. J. T. "Effects of tungsten on environmental systems". J.. PMID 16168748 . C.. Kluz.01.. S. H.. Peana. M. L. J. Vaughan. B. Christodoulatos. D. . Shen.. Chemosphere. 91. Oksuz. 61 (2): 248–58.. Braida. M. 90. Medici. P. Wu. Archaea: New Models for Prokaryotic Biology.083 . F. doi:10. Costa.. M. N. W (2005). Paul Blum.... A..89.1016/j.. Koutsospyros. Laulicht. D.. 92. Dermatas. I. J. S. M. A.. 24.1016/j. Koutsospyros."Tungsten-induced carcinogenesis in human bronchial epithelial cells" . Costa. Medici. Zoroddu. C. Laulicht. 93. Braida. N.. M. Peana. Lachowicz. Nurchi.... Toxicology and Applied Pharmacology..2015. (2017). 288 (1): 33–39. "Tungsten or Wolfram: Friend or Foe?" . M. Strigul. . M.07.2174/09298673246661704281056 03 . doi:10.taap.. (2006). Curr Med Chem. W. V. Christodoulatos..003 .. "A review of tungsten: From environmental obscurity to scrutiny". A. doi:10. J. doi:10. PMID 16343746 . p. doi:10.jhazmat. 136 (1): 1–19.007 . 39: 741–59.2005. CRC Press. 94. Molybdenum and tungsten: their roles in biological processes . 95. M. Leroy. Metal ions in biological systems. ISBN 0- 8247-0765-6. also reported in Astrid Sigel.Journal of Hazardous Materials.. Lagarde. Helmut Sigel (2002). "Tungsten and Selected Tungsten Compounds – Review of . Masten. F. (2002).1201/9780203909331. "Metabolism and toxicity of tungsten in humans and animals". PMID 11913143 .11.1016/j. 741 ff. Scott (2003).ch22 . Journal of forensic sciences. Marquet. 96. "CDC – NIOSH Pocket Guide to Chemical Hazards – Tungsten" . hair and nails by plasma emission spectrometry in a case of severe acute intoxication in man".gov. (1997). 42 (3): 527– 30. National Institute of Environmental Health Sciences. www. 97. "Tungsten determination in biological fluids. Archived from the original (PDF) on 2009- 03-25. Retrieved 2009-03-19.cdc..Toxicological Literature" (PDF). P. Retrieved 2015-11-24. Archived from the original on 2015-11-25. PMID 9144946 . et al. . ISBN 978-0- 8223-2188-0. General Electric Co.98. Guruswamy. McNeely. v. Jeffrey A. Protection of global biodiversity: converging strategies . 643 (3rd Cir. (1998).. De Forest Radio Co. 28 F. 1928) 99. Archived from the original on 2013-05-30.. Lakshman D. Duke University Press. External links .2d 641. pp. 333–. Photos. the free dictionary. Look up tungsten in Wiktionary. MSDS CDC – NIOSH Pocket Guide to Chemical Hazards Tungsten at The Periodic Table of Videos (University of Nottingham) Picture in the collection from Heinrich Pniok Elementymology & Elements Multidict by Peter van der Krogt – Tungsten .Wikimedia Commons has media related to Tungsten. Properties. History. org/w/index. International Tungsten Industry Association Retrieved from "https://en.php? title=Tungsten&oldid=821042750" Last edited 2 hours ago by Ira Leviton Content is available under CC BY-SA 3.0 unless otherwise noted.wikipedia. .