Tungsten: Properties, Production, Applications & Alloys Tungsten: Properties, Production, Applications & Alloys Search the site Tungsten: Properties, Production, Applications & Alloys What is tungsten? Updated October 18, 2016 Tungsten is a dull silver-coloured metal with the highest melting point of any pure metal. Also known as wolfram, from which the element takes its symbol, W, tungsten is more resistant to fracturing than diamond and is much harder than steel. It is the refractory metal's unique properties - its strength and ability to withstand high temperatures - that make it ideal for many commercial and industrial applications. Properties: Melting Point: 6192°F (3422°C) Boiling Point: 10031°F (5555°C) Moh's Hardness: 7.5 Production: Tungsten is primarily extracted from two types of minerals, wolframite, and scheelite. However, tungsten recycling also accounts for about 30% of the global supply. China is the world's largest producer of the metal, providing over 80% of the world supply.

Once tungsten ore has been processed and separated, the chemical form, ammonium paratungstate (APT), is produced. APT can be heated with hydrogen to form tungsten oxide or will react with carbon at temperatures above 1925°F (1050°C) to produce tungsten metal. Applications: Tungsten's primary application for over 100 years has been as the filament in incandescent light bulbs. Doped with small amounts of potassium-aluminum silicate, tungsten powder is sintered at high temperature to produce the wire filament that is in the center of light bulbs that light millions of homes around the world. Due to tungsten's ability to keep its shape at high temperatures, tungsten filaments are now also used in a variety of household applications, including lamps, floodlights, heating elements in electrical furnaces, microwave ovens, x-ray tubes and cathode-ray tubes (CRTs) in computer monitors and television sets. The metal's tolerance to intense heat also makes it ideal for thermocouples and electrical contacts in electric arc furnaces and welding equipment.

Applications that require a concentrated mass, or weight, such as counterweights, fishing sinkers, and darts often use tungsten because of its density. Tungsten Carbide: Tungsten carbide is produced either by bonding one tungsten atom with a single carbon atom (represented by the chemical symbol WC) or two tungsten atoms with a single carbon atom (W2C). This is done by heating tungsten powder with carbon at temperatures of 2550°F to 2900°F (1400°C to 1600°C) in a stream of hydrogen gas. According to Moh's hardness scale (a measure of one material's ability to scratch another), tungsten carbide has a hardness of 9.5, only slightly lower than diamond. For this reason, this hard compound is sintered, a process that requires pressing and heating the powder form at high temperatures, to make products used in machining and cutting. The result is materials that can operate in conditions of high temperature and stress, such as drill bits, lathe tools, milling cutters and armor piercing ammunition.

Cemented carbide is produced using a combination of tungsten carbide and cobalt powder, and is used to manufacture wear-resistant tools, such as those used in the mining industry. The tunnel-boring machine that was used to dig the Channel Tunnel linking Britain to Europe was, in fact, outfitted with almost 100 cemented carbide tips. Tungsten Alloys: Tungsten metal can be combined with other metals to increase their strength and resistance to wear and corrosion . Steel alloys often contain tungsten for these beneficial properties. Many high-speed steels -- those used in cutting and machining tools like saw blades -- contain around 18 percent tungsten. Tungsten-steel alloys are also used in the production of rocket engine nozzles, which must have high heat resistant properties. Other tungsten alloys include Stellite (cobalt, chromium, and tungsten), which is used in bearing and pistons due to its durability and resistance to wear, and Hevimet, which is made by sintering a tungsten alloy powder and is used in ammunition, dart barrels, and golf clubs. Superalloys made of cobalt, iron or nickel , along with tungsten, can be used to produce turbine blades for aircraft.

Continue Reading Tungsten, Chemical Element - uses, elements, metal, gas, number, name, symbol, mass Tungsten metal can be obtained by heating tungsten oxide (WO 3 ) with aluminum: It also results from passing hydrogen gas over hot tungstic acid (H 2 WO 4 ): Uses By far the most important use of tungsten is in making alloys. Tungsten is used to increase the hardness, strength, elasticity (flexibility), and tensile strength (ability to stretch) of steels. The metal is usually prepared in one of two forms. Ferrotungsten is an alloy of iron and tungsten. It usually contains about 70 to 80 percent tungsten. Ferrotungsten is mixed with other metals and alloys (usually steel) to make specialized alloys. Tungsten is also produced in powdered form. It can then be added to other metals to make alloys. About 90 percent of all tungsten alloys are used in mining, construction, and electrical and metalworking machinery. About 90 percent of all tungsten alloys are used in mining, construction, and electrical and metal-working machinery.

These alloys are used to make high-speed tools; heating elements in furnaces; parts for aircraft and spacecraft; equipment used in radio, television, and radar; rock drills; metal-cutting tools; and similar equipment. Tungsten alloys are used in radar equipment. Here, Doppler radar measures the speed and direction of local winds. A small, but very important, amount of tungsten is used to make incandescent lights. The very thin metal wire that makes up the filament in these lights is made of tungsten. An electric current passes through the wire, causing it to get hot and give off light. It does not melt because of the high melting point of tungsten. Compounds Probably the most important compound of tungsten is tungsten carbide (WC). Tungsten carbide has a very high melting point of 2,780°C (5,000°F). It is the strongest structural material. It is used to make parts for electrical circuits, cutting tools, cermets, and cemented carbide. A cermet is a material made of a ceramic and a metal. A ceramic is a clay-like material. Cermets are used where very high temperatures occur for long periods of time.

For example, the parts of a rocket motor or a jet engine may be made from a cermet. A cemented carbide is made by bonding tungsten carbide to another metal. The product is very strong and remains strong at high temperatures. Cemented carbides are used for rock and metal cutting. They can operate at 100 times the speed of similar tools made of steel. Health effects Tungsten has no essential role in the health of plants, humans, or animals. In moderate amounts, it also presents virtually no health danger. Also read article about Tungsten from Wikipedia User Contributions: Tungsten | Define Tungsten at Dictionary.com tungsten noun, Chemistry. 1. a rare, metallic element having a bright-gray color, a metallic luster, and a high melting point, 3410° C, and found in wolframite, tungstite , and other minerals: used in alloys of high-speed cutting tools, electric-lamp filaments, etc. Symbol: W; atomic weight: 183.85; atomic number: 74; specific gravity: 19.3.

Expand 1760-70; < Swedish, equivalent to tung heavy + sten stone Related forms [tuhng-sten-ik] /tʌŋˈstɛn ɪk/ (Show IPA), adjective Dictionary.com Unabridged Examples from the Web for tungsten Expand Helter Smelter No More: Moving to Conflict Free Minerals Intel June 25, 2014 Historical Examples The first tungsten lamps appeared on the market in 1906, but these contained fragile filaments made by the squirting process. How many candle power should a 20-watt tungsten lamp give if its efficiency is one watt per candle power? Physics Willis Eugene Tower The Ultimate Weapon John Wood Campbell British Dictionary definitions for tungsten Expand noun 1. a hard malleable ductile greyish-white element. It occurs principally in wolframite and scheelite and is used in lamp filaments, electrical contact points, X-ray targets, and, alloyed with steel, in high-speed cutting tools.

Symbol: W; atomic no: 74; atomic wt: 183.85; valency: 2–6; relative density: 19.3; melting pt: 3422±20°C; boiling pt: 5555°C Also called wolfram Word Origin C18: from Swedish tung heavy + stenstone Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Word Origin and History for tungsten Expand n. rare metallic element, 1796, from Swedish tungsten "calcium tungstate," coined by its discoverer, Swedish chemist Karl Wilhelm Scheele (1742-1786) from tung "heavy" + sten "stone." Used earlier as the name for calcium tungstate (1770).

Atomic symbol W is from Latin wolframium, from German Wolfram "iron tungstate" (see wolfram ). Online Etymology Dictionary, © 2010 Douglas Harper n. Symbol W A hard brittle corrosion-resistant metallic element having the highest melting point of any metal and used in high-temperature structural materials and in electrical elements, notably lamp filaments. Atomic number 74; atomic weight 183.85; melting point 3,422°C; boiling point 5,555°C; specific gravity 19.3 (20°C); valence 2, 3, 4, 5, 6. Also called wolfram. The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. (tŭng'stən) Symbol W A hard, gray to white metallic element that is very resistant to corrosion. It has the highest melting point of all elements, and it retains its strength at high temperatures.

It is used to make light-bulb filaments and to increase the hardness and strength of steel. Atomic number 74; atomic weight 183.84; melting point 3,410°C; boiling point 5,900°C; specific gravity 19.3 (20°C); valence 2, 3, 4, 5, 6. Also called wolfram. See Periodic Table . The American Heritage® Science Dictionary Copyright © 2002. Published by Houghton Mifflin. All rights reserved. W (element) | Article about W (element) by The Free Dictionary W (element) | Article about W (element) by The Free Dictionary Also found in: Dictionary , Thesaurus , Medical , Wikipedia . tungsten (tŭng`stən) [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410&degC;; b.p. 5,660&degC;; sp. gr.

19.3 at 20&degC;; valence +2, +3, +4, +5, or +6. Tungsten is a very hard, silver-white to steel-gray metal with a body-centered cubic crystalline structure. In its chemical properties it resembles molybdenum, the element above it in Group 6 of the periodic table periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled ..... Click the link for more information. . It is sometimes called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use of the name wolfram as a root is preferred. Tungsten is one of the most dense metals and has a higher melting point than any other metal. Pure tungsten is ductile, and wires made of it, even those of very small diameter, have a very high tensile strength. The element is resistant to ordinary acids and aqua regia but dissolves in a mixture of hydrofluoric and nitric acids.

It forms compounds with carbon, chlorine, oxygen, sulfur, and some other elements. It is hexavalent in its most important compounds. It forms tungstic acid (H2WO4), or wolframic acid, which is the basis of a series of salts called tungstates, or wolframates. Tungsten metal is used extensively for filaments for light bulbs and electronic tubes. Carboloy carboloy [portmanteau word from carbon and alloy], an alloy containing cobalt, tungsten, and carbon. This alloy is extremely hard, harder than steel; it is used to cut steel, porcelain, quartz, and other materials. ..... Click the link for more information. , stellite, and tungsten steels steel, alloy of iron, carbon, and small proportions of other elements. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese; steelmaking involves the removal of these impurities, known as slag, and the addition of desirable alloying elements. ..... Click the link for more information. are of importance in industry because they retain their hardness and strength at high temperatures.

Tungsten is usually added to steel in the form of ferrotungsten, obtained by the reduction of ferrous tungstate in an electric furnace. Tungsten carbide is used in place of diamond for dies and as an abrasive. Sodium wolframate is used in the fireproofing of fabrics, in the weighting of silk, and as a mordant in dyeing. Tungsten does not occur uncombined in nature; large deposits of its ores are found in various parts of the world. The trioxide occurs in nature as the mineral wolfram ochre; scheelite and wolframite wolframite , reddish-brown to grayish-black lustrous mineral, a tungstate of iron and manganese, (Fe,Mn)Wo4, occurring in crystals of the monoclinic system. It is the chief ore of the metal tungsten. ..... Click the link for more information. are the chief wolframate minerals. Tungsten is usually prepared from the trioxide by reduction with hydrogen or carbon. Tungsten was first isolated from tungstic acid in 1783 by the de Elhuyar brothers.

Tungsten W, a chemical element in Group VI of the Mendeleev periodic system. Atomic number, 74; atomic weight, 183.85. It is a refractory, heavy metal with a light gray color. Natural tungsten consists of a mixture of five stable isotopes with mass numbers 180, 182, 183, 184, and 186. Tungsten was discovered and isolated as tungstic oxide (WO3) in 1781 by the Swedish chemist K. Scheele from the mineral tungsten, which was later called scheelite. In 1783 the Spanish chemists, the brothers d’Elhuyar, prepared WO3 from the mineral wolframite and, by reducing WO3 with carbon, were the first to obtain the actual metal, which they called tungsten.

The actual mineral wolframite was also known to Agricola (16th century); he called it spuma lupi (wolfs cream) because tungsten, which always accompanies tin ores, interfered with the smelting of tin, converting it into the foam or scum of slags (“it devours tin as the wolf devours the sheep”). In the USA and some other countries the element was also called tungsten (Swedish, “heavy stone”). For a long time tungsten was not used industrially. It was only in the second half of the 19th century that the effects of tungsten on the properties of steel were investigated. Tungsten is sparsely distributed in nature; its content in the earth’s crust is 1 x 10~4 percent by weight. It does not occur in the free state, but forms its own minerals, mainly tung-states, among which wolframite, (Fe,Mn)WO4, and scheelite, CaWO4, are of industrial importance. Physical and chemical properties. Tungsten crystallizes in a body-centered cubic lattice system with dimension a = 3.1647 angstroms.

Density, 19.3 g/cm3; melting point, 3410° + 20° C; boiling point, 5900° C. Thermal conductivity (cal/cm - sec - ° C), 0.31 at 20° C and 0.26 at 1300° C; specific electrical resistance (ohms · cm x 10~6), 5.5 at 20° C and 90.4 at 2700° C; electron work function, 7.21 x 10~19 joules (J), or 4.55 electron volts (e V); high-temperature radiation coefficient (watts per sq cm), 18.0 at 1000° C, 64.0 at 2200° C, 153.0 at 2700° C, and 255.0 at 3030° C. The mechanical properties of tungsten depend on its previous treatment.

The tensile strength (kilograms-force per sq mm [kgf/mm2]) of sintered ingots is 11, and of pressure-treated ingots, 100-430; the elastic modulus is 35,000-38,000 in the case of wire and 39,000-41,000 for single-crystal threads. The Brinell hardness of sintered ingots is 200-230, and of forged ingots 350-400 (1 kgf/mm2 ≈ 10 meganewtons per sq m [MN/m2]). At room temperature the plasticity of tungsten is low. Under ordinary conditions tungsten is chemically stable. At 400°-500° C the dense metal is appreciably oxidized in air to WO3. Above 600° C steam oxidizes it vigorously to WO2. The halogens, sulfur, carbon, silicon, and boron react with tungsten at high temperatures; fluorine reacts with tungsten powder at room temperature.

Hydrogen does not react with tungsten at temperatures up to the melting point. Tungsten forms a nitride with nitrogen above 1500° C. Under ordinary conditions tungsten is resistant to hydrochloric, sulfuric, nitric, and hydrofluoric acids, as well as to aqua regia; at 100° C it reacts slightly with them, and it dissolves rapidly in a mixture of hydrofluoric and nitric acids. Upon heating, tungsten dissolves slightly in solutions of alkalies, and it dissolves rapidly in molten alkalies with the addition of air or oxidizing agents; tungstates are formed during this process. In its com-pounds tungsten has a valence of 2 to 6; the compounds of higher valence are the most stable. Tungsten forms four oxides, the highest of which is the trioxide WO3 (tungsten trioxide) and the lowest the dioxide WO2, with two intermediate oxides, W10O29 and W4O11. Tungsten trioxide is a lemon-yellow powder, which dissolves in solutions of alkalies with the formation of tungstates.

Upon reduction with hydrogen it yields the lower oxides and tungsten successively. Tungstic acid (H2WO4), a yellow powder that is virtually insoluble in water and acids, corresponds to tungsten trioxide. Solutions of tungstates are formed upon its reaction with solutions of alkalies and ammonia. At 188° C, H2WO4 loses water and forms WO3. Tungsten forms a series of chlorides and oxychlorides with chlorine. The most important are WC16 (melting point, 275° C; boiling point, 348° C) and WO2Cl2 (melting point, 266° C; sublimates above 300° C), which are produced by the action of chlorine on tungsten trioxide in the presence of carbon. Tungsten forms two sulfides with sulfur, WS2 and WS3.

The tungsten carbides WC (melting point, 2900° C) and W2C (melting point, 2750° C) are solid refractory compounds; they are produced from tungsten and carbon at 1000°-1500°C. Preparation and use. Wolframite and scheelite concentrates (50-60 percent WO3) are the raw material for the preparation of tungsten. Ferrotungsten (an alloy of iron with 65-80 per-cent tungsten), which is used in steel production, is smelted directly from the concentrates; tungsten trioxide is smelted out to obtain tungsten and its alloys and compounds. Several methods are used in industry to obtain WO3.

Scheelite concentrates are decomposed by a soda solution at 180°-200° C in autoclaves (to produce an industrial solution of sodium tungstate) or with hydrochloric acid (to produce industrial tungstic acid): (1) CaWO4 (solid) + Na2CO3 (liquid) = Na2WO4 (liquid) + CaCO3 (solid) (2) CaWO4 (solid) +2HC1 (liquid) = H2WO4 (solid) + CaCl2 (liquid) Wolframite concentrates are decomposed either by sintering with soda at 800°-900° C, followed by leaching of the Na2WO4 with water, or by heating with a caustic soda solution. Decomposition with alkaline reagents (soda or caustic soda) yields a solution of Na2WO4 that contains impurities. After the impurities are removed, H2WO4 is isolated from the solution.

(To produce precipitates that are coarser and easier to filter and wash, CaWO4 is first precipitated from the Na2WO4 solution and then decomposed with hydrochloric acid.) The dried H2WO4 contains 0.2-0.3 percent impurities. Calcination of H2WO4 at 700°-800° C yields WO3, from which hard alloys may be produced. To produce metallic tungsten, H2WO4 is further purified by the ammonia method—that is, by dissolving it in ammonia and crystallizing ammonium paratungstate, 5(NH4)2O · 12WO3 · «H2O. Calcination of this salt yields pure WO3. Tungsten powder is produced by the reduction of WO3 by hydrogen (carbon is also used in making hard metals) in electric tube furnaces at 700°-850° C. Compact metal is made from the powder by the powder metallurgy method—that is, by compressing in steel molds at pressures of 3-5 tons-force per sq cm and heat treatment of the billets.

The final stage of the heat treatment, heating to about 3000° C, is performed in special apparatus, with direct passage of an electrical current through the billets in a hydrogen atmosphere. Tungsten that lends itself well to pressure treatment (forging, drawing, and rolling) after heating is produced as a result of this process. Single tungsten crystals are obtained from the billets by the method of crucibleless electron-beam zone melting. In modern technology, tungsten is widely used both as pure metal and in the form of a number of alloys, the most important of which are alloyed steels, hard alloys based on tungsten carbide, and wear-resistant and temperature-resistant alloys. Tungsten is a component of a number of wear-resistant alloys used for coating the surfaces of machine parts (valves in airplane engines; turbine blades; and so on). Temperature-resistant alloys of tungsten with other refractory metals are used in aviation and rocketry. Its high melting point and low vapor pressure at high temperatures make tungsten indispensable for electric light filaments, as well as for making parts of vacuum-electrical devices in radio electronics and X-ray technology.

Several chemical compounds of tungsten are used in different fields of technology—for example, Na2WO4 in the paint and varnish and textile indus-tries, and WS2 as a catalyst in organic synthesis and an efficient solid lubricant for parts exposed to friction. REFERENCES Tungsten - Element information, properties and uses | Periodic Table Chemistry in its element: tungsten (Promo) You're listening to Chemistry in its element brought to you by Chemistry World, the magazine of the Royal Society of Chemistry. (End promo) Chris Smith Hello, this week supersonic steels, fast formula cars and upset Spanish scientists. But what are they arguing about? Here's Katherine Holt. Katherine Holt What's in a name? How do we decide what to call an element anyway? Is the name of an element the same in all languages? Does it matter? And who decides? Well the answer to the last question is easy - the naming of elements is ultimately decided by IUPAC - the International Union for Pure and Applied Chemistry. The answer to the other questions is mainly 'it depends'! Take for example the case of element 74 - or as we call it in English - tungsten. Ever wonder why its symbol is W?

Chemists in many European countries don't have to wonder why - because they call it Wolfram. The two-name confusion arises from early mineralogy. The name 'tungsten' is derived from the old Swedish name for 'heavy stone', a name given to a known tungsten-containing mineral. The name 'wolfram' comes from a different mineral, wolframite, which also has a high content of the element we call tungsten. Until recently both names - tungsten and wolfram - were included in 'Nomenclature of Inorganic Chemistry - IUPAC Recommendations' or the 'Red book' as it is known in IUPAC circles. However in 2005 'wolfram' was dropped and tungsten became the sole official IUPAC name for this element. However, wolfram did not go down without a fight! In particular the Spanish chemists were unhappy to see the change - not least because their compatriots the Delhuyar brothers are credited with the discovery of the element and its isolation from the mineral wolframite.

In their original paper, the Delhuyar brothers requested the name wolfram for the newly isolated element, saying 'We will call this new metal wolfram, taking its name from the matter of which it has been extracted.this name is more suitable than tungsten...... because wolframite is a mineral which was known long before...., at least among the mineralogists, and also because the name wolfram is accepted in almost all European languages....." Although this may be a compelling case, IUPAC argues that is that its working language is English and so Tungsten is the most appropriate name. They make the point that students will have to learn some history of chemistry to know why the element symbol is W. The same is true also for a number of other elements, such as potassium, mercury, and silver whose symbols bear no relation to their English name. However, it seems unlikely to me that such a colourful name as wolfram will be forgotten. In case you were wondering, it is believed to be derived from the German for 'wolf's foam'. Many centuries ago mid-European tin smelters observed that when a certain mineral was present in the tin ore, their yield of tin was much reduced.

They called this mineral 'wolfs foam' because, they said, it devoured the tin much like a wolf would devour a sheep! Thus over time the name 'wolframite' evolved for this tungsten-containing ore. In contrast to its semi-mythical role in early metallurgy, these days the applications of tungsten are highly technological, making use of its hardness, stability and high melting point. Current uses are as electrodes, heating elements and field emitters, and as filaments in light bulbs and cathode ray tubes. Tungsten is commonly used in heavy metal alloys such as high speed steel, from which cutting tools are manufactured. It is also used in the so-called 'superalloys' to form wear-resistant coatings. Its density makes it useful as ballast in aircraft and in Formula one cars and more controversially as supersonic shrapnel and armour piercing ammunition in missiles. It seems to me that the name tungsten, or 'heavy stone', is justified by these applications, which exploit its strength and density. I'm glad, though, that the birth of chemistry in the activity of those ancient metallurgists and mineralogists is still celebrated by the use of the symbol W for element 74.

This ensures that we never forget that there was a time, not so long ago, when many chemical processes could only be explained through metaphor. Chris Smith I always used to remember tungsten's letter W as standing for the wrong symbol, but can you think of the one letter of the alphabet that isn't used in the periodic table? Now there's something to ponder on. In the meantime, thank you very much to UCL's Katherine Holt. Next week we'll meet the element that was introduced to the world in, its fair to say, a pretty unusual way. Brian Clegg The first hint the world had of the existence of Americium was not in a paper for a distinguished journal but on a children's radio quiz in 1945. Seaborg appeared as a guest on MBC's Quiz Kids show where one of the participants asked him if they produced any other new elements as well as plutonium and neptunium. As Seaborg was due to formally announce the discovery of Americium five days later he let slip its existence along with element 96.

Chris Smith And Brian Clegg will be telling the story of the radio active element americium and how it keeps homes safe in next week's Chemistry in its element, I hope you can join us. I'm Chris Smith, thank you for listening and goodbye. (Promo) Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.com . There's more information and other episodes of Chemistry in its element on our website at chemistryworld.org/elements . (End promo) Adopt-A-Element - Tungsten Adopt-A-Element ﻿Tungsten Chris Buse Tungsten, from the Latin "tung sten" meaning heavy stone. · · The atomic symbol is W. This is because it was formerly known as Wolfram, hence the W. · Tungsten is solid at room temperature. · It is part of the transitional metal family. · Discovered by Juan Jose in 1779. Atomic Number China is reported to have about 75% of the world's Tungsten. · It was called Wolfram, hence the W. · It is used in fluorescent light bulbs and rings. · It has the highest melting point of any other metal.

· Tungsten dissolves in a mixture of hydrofluoric and nitric acids. · It is added to steel to make it stronger. tungsten - definition and meaning tungsten Definitions from The American Heritage® Dictionary of the English Language, 4th Edition n. A hard, brittle, corrosion-resistant, gray to white metallic element extracted from wolframite, scheelite, and other minerals, having the highest melting point and lowest vapor pressure of any metal. Tungsten and its alloys are used in high-temperature structural materials; in electrical elements, notably lamp filaments; and in instruments requiring thermally compatible glass-to-metal seals. Atomic number 74; atomic weight 183.84; melting point 3,410°C; boiling point 5,900°C; specific gravity 19.3 (20°C); valence 2, 3, 4, 5, 6. Also called wolfram. See Table at element. from Wiktionary, Creative Commons Attribution/Share-Alike License n. a metallic chemical element (symbol W) with an atomic number of 74. The symbol is derived from the Latin word wolframium.

from the GNU version of the Collaborative International Dictionary of English n. A rare element of the chromium group found in certain minerals, as wolfram and scheelite, and isolated as a heavy steel-gray metal which is very hard and infusible. It has both acid and basic properties. When alloyed in small quantities with steel, it greatly increases its hardness. Symbol W (Wolframium). Atomic weight, 183.6. Specific gravity, 18. n. Scheelite, or calcium tungstate. from The Century Dictionary and Cyclopedia n. Metallic tungsten has been obtained by means of the electric furnace in a fused state, though not quite compact, and probably not quite pure. It is of rather bright gray color, with metallic luster, specific gravity 18.7, hard, but not sufficiently so to scratch glass, of very high melting-point and softening gradually before fusion, so that it may be welded.

It is little acted on by air or water at ordinary temperature, slowly attacked by hydrochloric, hydrofluoric, or sulphuric acid, rapidly by hydrochloric or hydrofluoric acid with addition of nitric acid, and when in powder burns in the air at a red heat. n. Chemical symbol, W; atomic weight, 183.5. A metal some of whose ores have long been known (see wolfram and scheelite), but they were supposed to be compounds of tin. n. The native tungstate of lime. from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved. n. a heavy grey-white metallic element; the pure form is used mainly in electrical applications; it is found in several ores including wolframite and scheelite Etymologies from The American Heritage® Dictionary of the English Language, 4th Edition Swedish : tung, heavy (from Old Norse thungr) + sten, stone (from Old Norse steinn).

from Wiktionary, Creative Commons Attribution/Share-Alike License From Swedish and Danish tung heavy, + sten stone (although neither language uses "tungsten" as the name of the element) Examples But at the tip, where the electric field created by applying a voltage to the tungsten is at its maximum, N2 molecules are driven away. Tungsten | Halo Nation | Fandom powered by Wikia Share There is more information available on this subject at Tungsten on the English Wikipedia . Tungsten, also called wolfram (/ˈwʊlfrəm/), is a chemical element that has the symbol W (German: Wolfram) and atomic number 74. A very hard, heavy, steel-gray to white transition metal, tungsten is found in several ores including wolframite and scheelite and is remarkable for its robust physical properties, especially the fact that it has the highest melting point of all the non-alloyed metals and the second highest of all the elements after carbon. The pure form is used mainly in electrical applications but its many compounds and alloys are widely used in many applications, most notably in light bulb filaments, in X-ray tubes (as both the filament and target), and in superalloys.

Tungsten is the only metal from the third transition series that is known to occur in biomolecules. Pure tungsten is steel-gray to tin-white and is a hard metal. Tungsten can be cut with a hacksaw when it is very pure (it is brittle and hard to work when impure) and is otherwise worked by forging, drawing, extruding, or sintering. Of all metals, this element has the highest melting point (3,422 °C) (6,192 °F), lowest vapor pressure, and the highest tensile strength. Tungsten has the lowest coefficient of thermal expansion of any pure metal. Its corrosion resistance is excellent and it can be attacked only slightly by most mineral acids. Tungsten metal forms a protective oxide when exposed to air but can be oxidized at high temperature. Steel alloyed with small quantities of tungsten greatly increases its toughness. UNSC Uses Element of the Week | Homeschool Institute of Science Homeschool Institute of Science March 10, 2016 Tungsten (W) has the highest melting point of any metal; well over 3000 degrees Celsius! It is hard, brittle, and very similar in appearance to Tin (Sn).

Tungsten comes from the Swedish, tung sten, meaning heavy stone. It was formally known as wolfram, hence the mineral wolframite that contains tungsten. China is thought to hold 3/4 of the world’s tungsten deposits. Because of tungsten’s high melting point it is perfect for use in light bulbs. It even works better than the carbonized bamboo that Edison initially used 🙂 Watch this amazing video to see how tungsten is pulled into a wire and then coiled to be used in incandescent bulbs. Incandescence means “glowing visible light.” — March 2, 2016 Radium is hot stuff! It was used in self-luminating paints on alarm clocks and other devices into the 1950s, when it fell out of use due to the radioactive impacts on the paint process employees. Its chemical symbol is Ra and its atomic number 88. This means it has 88 electrons 88 protons. Check out this video of a fantastic thrift store find! The famous Madam Currie discovered radium in 1898. Read a very interesting retrospective from the Atlantic Monthly on this once alluring but very dangerous element.

By Alchemist-hp (talk) – Own work, CC BY-SA 3.0 de, February 15, 2016 The element of the week this week is Gold. Gold’s chemical symbol is Au and its atomic number is 79. It is the most malleable and ductile of the metals. Its melting point is over 1000 degrees C! All of the refined gold in the world would easily fit under the Eifel Tower. Our friends from Nottingham visit a vault in London . Wait for the end of the video for more links to more gold videos. Learn how to identify fool’s gold , how to make a gold plated watch, and more! The image to the left is of gold crystals produced synthetically in the lab. Wolframium | Article about Wolframium by The Free Dictionary Wolframium | Article about Wolframium by The Free Dictionary Also found in: Dictionary , Thesaurus , Medical , Wikipedia . tungsten (tŭng`stən) [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p.

about 3,410&degC;; b.p. 5,660&degC;; sp. gr. 19.3 at 20&degC;; valence +2, +3, +4, +5, or +6. Tungsten is a very hard, silver-white to steel-gray metal with a body-centered cubic crystalline structure. In its chemical properties it resembles molybdenum, the element above it in Group 6 of the periodic table periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled ..... Click the link for more information. . It is sometimes called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use of the name wolfram as a root is preferred. Tungsten is one of the most dense metals and has a higher melting point than any other metal. Pure tungsten is ductile, and wires made of it, even those of very small diameter, have a very high tensile strength.

The element is resistant to ordinary acids and aqua regia but dissolves in a mixture of hydrofluoric and nitric acids. It forms compounds with carbon, chlorine, oxygen, sulfur, and some other elements. It is hexavalent in its most important compounds. It forms tungstic acid (H2WO4), or wolframic acid, which is the basis of a series of salts called tungstates, or wolframates. Tungsten metal is used extensively for filaments for light bulbs and electronic tubes. Carboloy carboloy [portmanteau word from carbon and alloy], an alloy containing cobalt, tungsten, and carbon. This alloy is extremely hard, harder than steel; it is used to cut steel, porcelain, quartz, and other materials. ..... Click the link for more information. , stellite, and tungsten steels steel, alloy of iron, carbon, and small proportions of other elements. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese; steelmaking involves the removal of these impurities, known as slag, and the addition of desirable alloying elements. ..... Click the link for more information.

are of importance in industry because they retain their hardness and strength at high temperatures. Tungsten is usually added to steel in the form of ferrotungsten, obtained by the reduction of ferrous tungstate in an electric furnace. Tungsten carbide is used in place of diamond for dies and as an abrasive. Sodium wolframate is used in the fireproofing of fabrics, in the weighting of silk, and as a mordant in dyeing. Tungsten does not occur uncombined in nature; large deposits of its ores are found in various parts of the world. The trioxide occurs in nature as the mineral wolfram ochre; scheelite and wolframite wolframite , reddish-brown to grayish-black lustrous mineral, a tungstate of iron and manganese, (Fe,Mn)Wo4, occurring in crystals of the monoclinic system. It is the chief ore of the metal tungsten. ..... Click the link for more information. are the chief wolframate minerals. Tungsten is usually prepared from the trioxide by reduction with hydrogen or carbon. Tungsten was first isolated from tungstic acid in 1783 by the de Elhuyar brothers.

Tungsten W, a chemical element in Group VI of the Mendeleev periodic system. Atomic number, 74; atomic weight, 183.85. It is a refractory, heavy metal with a light gray color. Natural tungsten consists of a mixture of five stable isotopes with mass numbers 180, 182, 183, 184, and 186. Tungsten was discovered and isolated as tungstic oxide (WO3) in 1781 by the Swedish chemist K. Scheele from the mineral tungsten, which was later called scheelite. In 1783 the Spanish chemists, the brothers d’Elhuyar, prepared WO3 from the mineral wolframite and, by reducing WO3 with carbon, were the first to obtain the actual metal, which they called tungsten.

The actual mineral wolframite was also known to Agricola (16th century); he called it spuma lupi (wolfs cream) because tungsten, which always accompanies tin ores, interfered with the smelting of tin, converting it into the foam or scum of slags (“it devours tin as the wolf devours the sheep”). In the USA and some other countries the element was also called tungsten (Swedish, “heavy stone”). For a long time tungsten was not used industrially. It was only in the second half of the 19th century that the effects of tungsten on the properties of steel were investigated. Tungsten is sparsely distributed in nature; its content in the earth’s crust is 1 x 10~4 percent by weight. It does not occur in the free state, but forms its own minerals, mainly tung-states, among which wolframite, (Fe,Mn)WO4, and scheelite, CaWO4, are of industrial importance. Physical and chemical properties. Tungsten crystallizes in a body-centered cubic lattice system with dimension a = 3.1647 angstroms.

Density, 19.3 g/cm3; melting point, 3410° + 20° C; boiling point, 5900° C. Thermal conductivity (cal/cm - sec - ° C), 0.31 at 20° C and 0.26 at 1300° C; specific electrical resistance (ohms · cm x 10~6), 5.5 at 20° C and 90.4 at 2700° C; electron work function, 7.21 x 10~19 joules (J), or 4.55 electron volts (e V); high-temperature radiation coefficient (watts per sq cm), 18.0 at 1000° C, 64.0 at 2200° C, 153.0 at 2700° C, and 255.0 at 3030° C. The mechanical properties of tungsten depend on its previous treatment.

The tensile strength (kilograms-force per sq mm [kgf/mm2]) of sintered ingots is 11, and of pressure-treated ingots, 100-430; the elastic modulus is 35,000-38,000 in the case of wire and 39,000-41,000 for single-crystal threads. The Brinell hardness of sintered ingots is 200-230, and of forged ingots 350-400 (1 kgf/mm2 ≈ 10 meganewtons per sq m [MN/m2]). At room temperature the plasticity of tungsten is low. Under ordinary conditions tungsten is chemically stable. At 400°-500° C the dense metal is appreciably oxidized in air to WO3. Above 600° C steam oxidizes it vigorously to WO2. The halogens, sulfur, carbon, silicon, and boron react with tungsten at high temperatures; fluorine reacts with tungsten powder at room temperature.

Hydrogen does not react with tungsten at temperatures up to the melting point. Tungsten forms a nitride with nitrogen above 1500° C. Under ordinary conditions tungsten is resistant to hydrochloric, sulfuric, nitric, and hydrofluoric acids, as well as to aqua regia; at 100° C it reacts slightly with them, and it dissolves rapidly in a mixture of hydrofluoric and nitric acids. Upon heating, tungsten dissolves slightly in solutions of alkalies, and it dissolves rapidly in molten alkalies with the addition of air or oxidizing agents; tungstates are formed during this process. In its com-pounds tungsten has a valence of 2 to 6; the compounds of higher valence are the most stable. Tungsten forms four oxides, the highest of which is the trioxide WO3 (tungsten trioxide) and the lowest the dioxide WO2, with two intermediate oxides, W10O29 and W4O11. Tungsten trioxide is a lemon-yellow powder, which dissolves in solutions of alkalies with the formation of tungstates.

Upon reduction with hydrogen it yields the lower oxides and tungsten successively. Tungstic acid (H2WO4), a yellow powder that is virtually insoluble in water and acids, corresponds to tungsten trioxide. Solutions of tungstates are formed upon its reaction with solutions of alkalies and ammonia. At 188° C, H2WO4 loses water and forms WO3. Tungsten forms a series of chlorides and oxychlorides with chlorine. The most important are WC16 (melting point, 275° C; boiling point, 348° C) and WO2Cl2 (melting point, 266° C; sublimates above 300° C), which are produced by the action of chlorine on tungsten trioxide in the presence of carbon. Tungsten forms two sulfides with sulfur, WS2 and WS3.

The tungsten carbides WC (melting point, 2900° C) and W2C (melting point, 2750° C) are solid refractory compounds; they are produced from tungsten and carbon at 1000°-1500°C. Preparation and use. Wolframite and scheelite concentrates (50-60 percent WO3) are the raw material for the preparation of tungsten. Ferrotungsten (an alloy of iron with 65-80 per-cent tungsten), which is used in steel production, is smelted directly from the concentrates; tungsten trioxide is smelted out to obtain tungsten and its alloys and compounds. Several methods are used in industry to obtain WO3.

Scheelite concentrates are decomposed by a soda solution at 180°-200° C in autoclaves (to produce an industrial solution of sodium tungstate) or with hydrochloric acid (to produce industrial tungstic acid): (1) CaWO4 (solid) + Na2CO3 (liquid) = Na2WO4 (liquid) + CaCO3 (solid) (2) CaWO4 (solid) +2HC1 (liquid) = H2WO4 (solid) + CaCl2 (liquid) Wolframite concentrates are decomposed either by sintering with soda at 800°-900° C, followed by leaching of the Na2WO4 with water, or by heating with a caustic soda solution. Decomposition with alkaline reagents (soda or caustic soda) yields a solution of Na2WO4 that contains impurities. After the impurities are removed, H2WO4 is isolated from the solution.

(To produce precipitates that are coarser and easier to filter and wash, CaWO4 is first precipitated from the Na2WO4 solution and then decomposed with hydrochloric acid.) The dried H2WO4 contains 0.2-0.3 percent impurities. Calcination of H2WO4 at 700°-800° C yields WO3, from which hard alloys may be produced. To produce metallic tungsten, H2WO4 is further purified by the ammonia method—that is, by dissolving it in ammonia and crystallizing ammonium paratungstate, 5(NH4)2O · 12WO3 · «H2O. Calcination of this salt yields pure WO3. Tungsten powder is produced by the reduction of WO3 by hydrogen (carbon is also used in making hard metals) in electric tube furnaces at 700°-850° C. Compact metal is made from the powder by the powder metallurgy method—that is, by compressing in steel molds at pressures of 3-5 tons-force per sq cm and heat treatment of the billets.

The final stage of the heat treatment, heating to about 3000° C, is performed in special apparatus, with direct passage of an electrical current through the billets in a hydrogen atmosphere. Tungsten that lends itself well to pressure treatment (forging, drawing, and rolling) after heating is produced as a result of this process. Single tungsten crystals are obtained from the billets by the method of crucibleless electron-beam zone melting. In modern technology, tungsten is widely used both as pure metal and in the form of a number of alloys, the most important of which are alloyed steels, hard alloys based on tungsten carbide, and wear-resistant and temperature-resistant alloys. Tungsten is a component of a number of wear-resistant alloys used for coating the surfaces of machine parts (valves in airplane engines; turbine blades; and so on). Temperature-resistant alloys of tungsten with other refractory metals are used in aviation and rocketry. Its high melting point and low vapor pressure at high temperatures make tungsten indispensable for electric light filaments, as well as for making parts of vacuum-electrical devices in radio electronics and X-ray technology.

Several chemical compounds of tungsten are used in different fields of technology—for example, Na2WO4 in the paint and varnish and textile indus-tries, and WS2 as a catalyst in organic synthesis and an efficient solid lubricant for parts exposed to friction. REFERENCES

Question: What element has the highest melting point of any metal - symbol W, otherwise known as wolfram?
Answer: Tungsten