113-464: The Centennial Light is an incandescent light bulb recognized as the oldest known continuously operating light bulb. It was first illuminated in 1901, and has only been turned off a few brief times since. It is located at 4550 East Avenue, Livermore, California , and is open to public viewing. Due to its longevity, the bulb has been noted by The Guinness Book of World Records , Ripley's Believe It or Not! , and General Electric . The light has been
226-425: A body-centered cubic structure and is the more stable form. The structure of the β phase is called A15 cubic ; it is metastable , but can coexist with the α phase at ambient conditions owing to non-equilibrium synthesis or stabilization by impurities. Contrary to the α phase which crystallizes in isometric grains, the β form exhibits a columnar habit . The α phase has one third of the electrical resistivity and
339-407: A phase-out of incandescent light bulbs to reduce energy consumption. Historians Robert Friedel and Paul Israel list inventors of incandescent lamps prior to Joseph Swan and Thomas Edison of General Electric . They conclude that Edison's version was the first practical implementation, able to outstrip the others because of a combination of four factors: an effective incandescent material;
452-437: A sextuple bond between tungsten atoms — the highest known bond order among stable atoms. In 1781, Carl Wilhelm Scheele discovered that a new acid , tungstic acid , could be made from scheelite (at the time called tungsten). Scheele and Torbern Bergman suggested that it might be possible to obtain a new metal by reducing this acid. In 1783, José and Fausto Elhuyar found an acid made from wolframite that
565-434: A vacuum higher than other implementations which was achieved through the use of a Sprengel pump ; a high resistance that made power distribution from a centralized source economically viable, and the development of the associated components required for a large-scale lighting system. Historian Thomas Hughes has attributed Edison's success to his development of an entire, integrated system of electric lighting. The lamp
678-428: A Canadian patent was filed by Henry Woodward and Mathew Evans for a lamp consisting of carbon rods mounted in a nitrogen-filled glass cylinder. They were unsuccessful at commercializing their lamp, and sold rights to their patent to Thomas Edison in 1879. (Edison needed ownership of the novel claim of lamps connected in a parallel circuit.) The government of Canada maintains that it is Woodward and Evans who invented
791-493: A Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen slows down the evaporation of the tungsten filament compared to operating it in
904-501: A US court rejected General Electric 's attempt to patent it, overturning U.S. patent 1,082,933 granted in 1913 to William D. Coolidge . It is suggested that remnants of wolfram have been found in what may have been the garden of the astronomer/alchemist Tycho Brahe The name tungsten (which means ' heavy stone ' in Swedish and was the old Swedish name for the mineral scheelite and other minerals of similar density)
1017-438: A broader array of light sources. The spectrum of light produced by an incandescent lamp closely approximates that of a black body radiator at the same temperature. The basis for light sources used as the standard for color perception is a tungsten incandescent lamp operating at a defined temperature. Tungsten Tungsten (also called wolfram ) is a chemical element ; it has symbol W and atomic number 74. It
1130-513: A carbon conductor, and platinum lead-in wires. This bulb lasted about 40 hours. Swan then turned his attention to producing a better carbon filament and the means of attaching its ends. He devised a method of treating cotton to produce 'parchmentised thread' in the early 1880s and obtained British Patent 4933 that same year. From this year he began installing light bulbs in homes and landmarks in England. His house, Underhill, Low Fell, Gateshead ,
1243-472: A carbonized bamboo filament could last more than 1200 hours. In 1880, the Oregon Railroad and Navigation Company steamer, Columbia , became the first application for Edison's incandescent electric lamps (it was also the first ship to use a dynamo ). Albon Man, a New York lawyer, started Electro-Dynamic Light Company in 1878 to exploit his patents and those of William Sawyer . Weeks later
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#17327809405761356-466: A coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum, improving its longevity. Although a workable design, the cost of the platinum made it impractical for commercial use. In 1841, Frederick de Moleyns of England
1469-568: A colorless gas. At around 250 °C it will react with chlorine or bromine, and under certain hot conditions will react with iodine. Finely divided tungsten is pyrophoric . The most common formal oxidation state of tungsten is +6, but it exhibits all oxidation states from −2 to +6. Tungsten typically combines with oxygen to form the yellow tungstic oxide , WO 3 , which dissolves in aqueous alkaline solutions to form tungstate ions, WO 4 . Tungsten carbides (W 2 C and WC) are produced by heating powdered tungsten with carbon. W 2 C
1582-504: A constant electric light at a public meeting in Dundee, Scotland . He stated that he could "read a book at a distance of one and a half feet". However he did not develop the electric light any further. In 1838, Belgian lithographer Marcellin Jobard invented an incandescent light bulb with a vacuum atmosphere using a carbon filament. In 1840, British scientist Warren De la Rue enclosed
1695-426: 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 H 3 PW 12 O 40 . Tungsten trioxide can form intercalation compounds with alkali metals. These are known as bronzes ; an example is sodium tungsten bronze . In gaseous form, tungsten forms the diatomic species W 2 . These molecules feature
1808-478: A glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the US, changed his name to Alexander de Lodyguine and applied for and obtained patents for incandescent lamps having chromium , iridium , rhodium , ruthenium , osmium , molybdenum and tungsten filaments. On 24 July 1874,
1921-422: A half-life of (1.8 ± 0.2) × 10 years; on average, this yields about two alpha decays of W per gram of natural tungsten per year. This rate is equivalent to a specific activity of roughly 63 micro- becquerel per kilogram. This rate of decay is orders of magnitude lower than that observed in carbon or potassium as found on earth, which likewise contain small amounts of long-lived radioactive isotopes. Bismuth
2034-448: A lamp with inert gas instead of a vacuum resulted in twice the luminous efficacy and reduced bulb blackening. In 1917, Burnie Lee Benbow was granted a patent for the coiled coil filament , in which a coiled filament is then itself wrapped into a coil by use of a mandrel . In 1921, Junichi Miura created the first double-coil bulb using a coiled coil tungsten filament while working for Hakunetsusha (a predecessor of Toshiba ). At
2147-406: A lower resistivity than carbon, the tantalum lamp filament was quite long and required multiple internal supports. The metal filament gradually shortened in use; the filaments were installed with large slack loops. Lamps used for several hundred hours became quite fragile. Metal filaments had the property of breaking and re-welding, though this would usually decrease resistance and shorten the life of
2260-486: A meeting of the Literary and Philosophical Society of Newcastle upon Tyne on 3 February 1879. These lamps used a carbon rod from an arc lamp rather than a slender filament. Thus they had low resistance and required very large conductors to supply the necessary current, so they were not commercially practical, although they did furnish a demonstration of the possibilities of incandescent lighting with relatively high vacuum,
2373-638: A much lower superconducting transition temperature T C relative to the β phase: ca. 0.015 K vs. 1–4 K; mixing the two phases allows obtaining intermediate T C values. The T C value can also be raised by alloying tungsten with another metal (e.g. 7.9 K for W- Tc ). Such tungsten alloys are sometimes used in low-temperature superconducting circuits. Naturally occurring tungsten consists of four stable isotopes ( W, W, W, and W) and one very long-lived radioisotope, W. Theoretically, all five can decay into isotopes of element 72 ( hafnium ) by alpha emission , but only W has been observed to do so, with
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#17327809405762486-698: A process of introducing red phosphorus as the so-called getter inside the bulb ), which allowed obtaining economic bulbs lasting 800 hours; his patent was acquired by Edison in 1898. In 1897, German physicist and chemist Walther Nernst developed the Nernst lamp , a form of incandescent lamp that used a ceramic globar and did not require enclosure in a vacuum or inert gas. Twice as efficient as carbon filament lamps, Nernst lamps were briefly popular until overtaken by lamps using metal filaments. US575002A patent on 01.Dec.1897 to Alexander Lodyguine (Lodygin, Russia) describes filament made of rare metals, amongst them
2599-534: A range of oxidation states. Notable examples include the trigonal prismatic W(CH 3 ) 6 and octahedral W(CO) 6 . The world's reserves of tungsten are 3,200,000 tonnes; they are mostly located in China (1,800,000 t), Canada (290,000 t), Russia (160,000 t), Vietnam (95,000 t) and Bolivia . As of 2017, China, Vietnam and Russia are the leading suppliers with 79,000, 7,200 and 3,100 tonnes, respectively. Canada had ceased production in late 2015 due to
2712-424: A result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps , and flashlights , and for decorative and advertising lighting. Incandescent bulbs are much less efficient than other types of electric lighting. Less than 5% of the energy they consume is converted into visible light; the rest is lost as heat. The luminous efficacy of
2825-402: A ruling 8 October 1883, that Edison's patents were based on the prior art of William Sawyer and were invalid. Litigation continued for a number of years. Eventually on 6 October 1889, a judge ruled that Edison's electric light improvement claim for "a filament of carbon of high resistance" was valid. The main difficulty with evacuating the lamps was moisture inside the bulb, which split when
2938-487: A sharp blow. The hardness and heat resistance of tungsten can contribute to useful alloys . A good example is high-speed steel , which can contain as much as 18% tungsten. Tungsten's high melting point makes tungsten a good material for applications like rocket nozzles , for example in the UGM-27 Polaris submarine-launched ballistic missile . Tungsten alloys are used in a wide range of applications, including
3051-488: A shortage of tungsten used in the shell core, caused in part by the Wolfram Crisis , limited their use. Tungsten has also been used in dense inert metal explosives , which use it as dense powder to reduce collateral damage while increasing the lethality of explosives within a small radius. Tungsten(IV) sulfide is a high temperature lubricant and is a component of catalysts for hydrodesulfurization . MoS 2
3164-421: A source is defined as the ratio of its luminous efficacy to the maximum possible luminous efficacy, which is 683 lm/W. An ideal white light source could produce about 250 lumens per watt, corresponding to a luminous efficiency of 37%. For a given quantity of light, an incandescent light bulb consumes more power and emits more heat than most other types of electric light. In buildings where air conditioning
3277-478: A story on the bulb, generating visitors and general interest, then it will drop back into obscurity for a while. Dozens of magazines and newspapers have featured articles on the bulb. The bulb has been visited and featured by many major news channels in the United States, including NBC , ABC , Fox , CBS , WB , CNN and NPR . The bulb has received letters acknowledging and celebrating its longevity from
3390-527: A successful version of this the first synthetic filament. The light bulb invented by Cruto lasted five hundred hours as opposed to the forty of Edison's original version. In 1882 Munich Electrical Exhibition in Bavaria, Germany Cruto's lamp was more efficient than the Edison's one and produced a better, white light. In 1893, Heinrich Göbel claimed he had designed the first incandescent light bulb in 1854, with
3503-480: A system of lighting . In 1761, Ebenezer Kinnersley demonstrated heating a wire to incandescence . However such wires tended to melt or oxidize very rapidly (burn) in the presence of air. Limelight became a popular form of stage lighting in the early 19th century, by heating a piece of calcium oxide to incandescence with an oxyhydrogen torch . In 1802, Humphry Davy used what he described as "a battery of immense size", consisting of 2,000 cells housed in
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3616-476: A thin carbonized bamboo filament of high resistance, platinum lead-in wires in an all-glass envelope, and a high vacuum. Judges of four courts raised doubts about the alleged Göbel anticipation , but there was never a decision in a final hearing due to the expiration of Edison's patent. Research work published in 2007 concluded that the story of the Göbel lamps in the 1850s is fictitious. Joseph Swan (1828–1914)
3729-499: A tungsten bar with gold, which has been observed since the 1980s, or taking an existing gold bar, drilling holes, and replacing the removed gold with tungsten rods. The densities are not exactly the same, and other properties of gold and tungsten differ, but gold-plated tungsten will pass superficial tests. Gold-plated tungsten is available commercially from China (the main source of tungsten), both in jewelry and as bars. Because it retains its strength at high temperatures and has
3842-936: A typical incandescent bulb for 120 V operation is 16 lumens per watt (lm/W), compared with 60 lm/W for a compact fluorescent bulb or 100 lm/W for typical white LED lamps . The heat produced by filaments is used in some applications, such as heat lamps in incubators , lava lamps , Edison effect bulbs, and the Easy-Bake Oven toy. Quartz envelope halogen infrared heaters are used for industrial processes such as paint curing and space heating. Incandescent bulbs typically have shorter lifetimes compared to other types of lighting; around 1,000 hours for home light bulbs versus typically 10,000 hours for compact fluorescents and 20,000–30,000 hours for lighting LEDs. Most incandescent bulbs can be replaced by fluorescent lamps , high-intensity discharge lamps , and light-emitting diode lamps (LED). Some governments have begun
3955-453: A vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life. In 1906, William D. Coolidge developed a method of making "ductile tungsten" from sintered tungsten which could be made into filaments while working for General Electric Company . By 1911 General Electric had begun selling incandescent light bulbs with ductile tungsten wire. In 1913, Irving Langmuir found that filling
4068-414: Is hypoallergenic , and is harder than gold alloys (though not as hard as tungsten carbide), making it useful for rings that will resist scratching, especially in designs with a brushed finish . Because the density is so similar to that of gold (tungsten is only 0.36% less dense), and its price of the order of one-thousandth, tungsten can also be used in counterfeiting of gold bars , such as by plating
4181-475: Is selective laser melting , which is a form of 3D printing and allows creating complex three-dimensional shapes. Tungsten is mainly used in the production of hard materials based on tungsten carbide (WC), one of the hardest carbides . WC is an efficient electrical conductor , but W 2 C is less so. WC is used to make wear-resistant abrasives , and "carbide" cutting tools such as knives, drills, circular saws , dies , milling and turning tools used by
4294-502: Is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a distinct element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite , the latter lending the element its alternative name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements, melting at 3,422 °C (6,192 °F; 3,695 K). It also has
4407-476: Is heated with hydrogen or carbon to produce powdered tungsten. 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 WF 6 : or pyrolytic decomposition : Tungsten
4520-484: Is in tungsten carbide , a wear-resistant metal used in metalworking , mining , and construction . About 50% of tungsten is used in tungsten carbide, with the remaining major use being alloys and steels: less than 10% is used other compounds. Tungsten is the only metal in the third transition series that is known to occur in biomolecules , being found in a few species of bacteria and archaea . However, tungsten interferes with molybdenum and copper metabolism and
4633-465: Is more ductile and can be cut with a hard-steel hacksaw . Tungsten occurs in many alloys, which have numerous applications, including incandescent light bulb filaments, X-ray tubes , electrodes in gas tungsten arc welding , superalloys , and radiation shielding . Tungsten's hardness and high density make it suitable for military applications in penetrating projectiles . Tungsten compounds are often used as industrial catalysts . Its largest use
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4746-642: Is more commonly used for such applications. Tungsten oxides are used in ceramic glazes and calcium / magnesium tungstates are used widely in fluorescent lighting . Crystal tungstates are used as scintillation detectors in nuclear physics and nuclear medicine . Other salts that contain tungsten are used in the chemical and tanning industries. Tungsten oxide (WO 3 ) is incorporated into selective catalytic reduction (SCR) catalysts found in coal-fired power plants. These catalysts convert nitrogen oxides ( NO x ) to nitrogen (N 2 ) and water (H 2 O) using ammonia (NH 3 ). The tungsten oxide helps with
4859-498: Is not traded as a futures contract and cannot be tracked on exchanges like the London Metal Exchange . The tungsten industry often uses independent pricing references such as Argus Media or Metal Bulletin as a basis for contracts. The prices are usually quoted for tungsten concentrate or WO 3 . Approximately half of the tungsten is consumed for the production of hard materials – namely tungsten carbide – with
4972-663: Is problematic even in depleted form, or where uranium's additional pyrophoric properties are not desired (for example, in ordinary small arms bullets designed to penetrate body armor). Similarly, tungsten alloys have also been used in shells , grenades , and missiles , to create supersonic shrapnel. Germany used tungsten during World War II to produce shells for anti-tank gun designs using the Gerlich squeeze bore principle to achieve very high muzzle velocity and enhanced armor penetration from comparatively small caliber and light weight field artillery. The weapons were highly effective but
5085-426: Is resistant to chemical attack, although it reacts strongly with chlorine to form tungsten hexachloride (WCl 6 ). In aqueous solution, tungstate gives the heteropoly acids and polyoxometalate anions under neutral and acidic conditions. As tungstate is progressively treated with acid, it first yields the soluble, metastable "paratungstate A" anion , W 7 O 24 , which over time converts to
5198-450: Is somewhat toxic to most forms of animal life. In its raw form, tungsten is a hard steel-grey metal that is often brittle and hard to work . Purified, monocrystalline tungsten retains its hardness (which exceeds that of many steels), and becomes malleable enough that it can be worked easily. It is worked by forging , drawing , or extruding but it is more commonly formed by sintering . Of all metals in pure form, tungsten has
5311-638: Is strictly regulated by the Chinese Government, which fights illegal mining and excessive pollution originating from mining and refining processes. 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 . Following increases in tungsten prices, this mine was reactivated in 2014, but ceased activities in 2018. Within
5424-544: Is used in English, French, and many other languages as the name of the element, but wolfram (or volfram ) is used in most European (especially Germanic and Slavic) languages and is derived from the mineral wolframite , which is the origin of the chemical symbol W . The name wolframite is derived from German wolf rahm ( ' wolf soot, wolf cream ' ), the name given to tungsten by Johan Gottschalk Wallerius in 1747. This, in turn, derives from Latin lupi spuma ,
5537-411: Is used, incandescent lamps' heat output increases load on the air conditioning system. While heat from lights will reduce the need to run a building's heating system, the latter can usually produce the same amount of heat at lower cost than incandescent lights. The chart below lists the luminous efficacy and efficiency for several types of incandescent bulb. A longer chart in luminous efficacy compares
5650-709: The Carrock mine from the German owned Cumbrian Mining Company and, during World War I , restrict German access elsewhere. In World War II , tungsten played a more significant role in background political dealings. Portugal, as the main European source of the element, was put under pressure from both sides , because of its deposits of wolframite ore at Panasqueira . Tungsten's desirable properties such as resistance to high temperatures, its hardness and density, and its strengthening of alloys made it an important raw material for
5763-599: The EU , the Austrian Felbertal scheelite deposit is one of the few producing tungsten mines. Portugal is one of Europe's main tungsten producers, with 121 kt of contained tungsten in mineral concentrates from 1910 to 2020, accounting for roughly 3.3% of the global production. Tungsten is considered to be a conflict mineral due to the unethical mining practices observed in the Democratic Republic of
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#17327809405765876-606: The Edison and Swan United Electric Company (later known as Ediswan, and ultimately incorporated into Thorn Lighting Ltd ). Edison was initially against this combination, but Edison was eventually forced to cooperate and the merger was made. Eventually, Edison acquired all of Swan's interest in the company. Swan sold his US patent rights to the Brush Electric Company in June 1882. The United States Patent Office gave
5989-604: The Guinness Book of World Records as "the most durable light" in 1972, replacing the Palace Theater Light in Fort Worth, Texas . The bulb was listed in the book for the next 16 editions. It was not listed during 1988–2006, without a reason being given, before returning in 2007. At least four books have been written about the bulb. According to the fire chief, every few months a news outlet will publish
6102-796: The United States Electric Lighting Company was organized. This company did not make their first commercial installation of incandescent lamps until the fall of 1880, at the Mercantile Safe Deposit Company in New York City, about six months after the Edison incandescent lamps had been installed on the Columbia . Hiram S. Maxim was the chief engineer at the US Electric Lighting Co. After the great success in
6215-570: The electric arc , by passing high current between two pieces of charcoal. For the next 40 years much research was given to turning the carbon arc lamp into a practical means of lighting. The carbon arc itself was dim and violet in color, emitting most of its energy in the ultraviolet, but the positive electrode was heated to just below the melting point of carbon and glowed very brightly with incandescence very close to that of sunlight. Arc lamps burned up their carbon rods very rapidly, expelled dangerous carbon monoxide, and tended to produce outputs in
6328-473: The Congo . South Korea's Sangdong mine , one of the world's largest tungsten mines with 7,890,000 tonnes of high-grade tungsten reportedly buried, was closed in 1994 due to low profitability but has since re-registered mining rights and is scheduled to resume activities in 2024. Tungsten is extracted from its ores in several stages. The ore is eventually converted to tungsten(VI) oxide (WO 3 ), which
6441-772: The United States, the incandescent light bulb patented by Edison also began to gain widespread popularity in Europe as well; among other places, the first Edison light bulbs in the Nordic countries were installed at the weaving hall of the Finlayson 's textile factory in Tampere, Finland in March 1882. Lewis Latimer , employed at the time by Edison, developed an improved method of heat-treating carbon filaments which reduced breakage and allowed them to be molded into novel shapes, such as
6554-417: The aerospace and automotive industries and radiation shielding. Superalloys containing tungsten, such as Hastelloy and Stellite , are used in turbine blades and wear-resistant parts and coatings. Tungsten's heat resistance makes it useful in arc welding applications when combined with another highly-conductive metal such as silver or copper. The silver or copper provides the necessary conductivity and
6667-422: The arms industry, both as a constituent of weapons and equipment and employed in production itself, e.g., in tungsten carbide cutting tools for machining steel. Now tungsten is used in many more applications such as aircraft and motorsport ballast weights, darts, anti-vibration tooling, and sporting equipment. Tungsten is unique amongst the elements in that it has been the subject of patent proceedings. In 1928,
6780-469: The basement of the Royal Institution of Great Britain, to create an incandescent light by passing the current through a thin strip of platinum , chosen because the metal had an extremely high melting point . It was not bright enough nor did it last long enough to be practical, but it was the precedent behind the efforts of scores of experimenters over the next 75 years. Davy also demonstrated
6893-400: The bulb for the rest of its life, regardless of length. When it does go out, they have no plans for it, although Ripley's Believe it or Not! has requested it for their museum. Several reasons have been cited for the bulb's extensive lifespan. Its continuous operation has largely eliminated the stresses associated with turning a light bulb on and off, the act of which causes the temperature of
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#17327809405767006-420: The bulb to increase and decrease. The bulb was made by hand, using a carbon filament (of greater thickness and strength than the tungsten filaments used in most modern lightbulbs) along with brass and glass components of high quality. The low wattage (originally 60 watts, now approximately four) and high nitrogen atmosphere inside the bulb have also contributed to its longevity. The bulb was officially listed in
7119-423: The bulb to the fire station when he sold the company. That story has been supported by firefighter volunteers of that era. Evidence suggests that the bulb has hung in at least four locations. It was originally hung in 1901 in a hose cart house on L Street, then moved to a garage in downtown Livermore used by the fire and police departments. The bulb was saved during the fire station's 1937 renovation, during which it
7232-521: The characteristic "M" shape of Maxim filaments. On 17 January 1882, Latimer received a patent for the "Process of Manufacturing Carbons", an improved method for the production of light bulb filaments, which was purchased by the United States Electric Light Company. Latimer patented other improvements such as a better way of attaching filaments to their wire supports. In Britain, the Edison and Swan companies merged into
7345-722: The city of Shelby, Ohio , the Alameda County Board of Supervisors, the California State Assembly , the California State Senate , Congresswoman Ellen Tauscher , Senator Barbara Boxer , and President George W. Bush . The bulb was featured on an episode of MythBusters on December 13, 2006, in the PBS documentary Livermore and an episode of California's Gold with Huell Howser, in an episode of 99% Invisible , and mentioned in
7458-448: The closure of its sole tungsten mine. Meanwhile, Vietnam had significantly increased its output in the 2010s, owing to the major optimization of its domestic refining operations, and overtook Russia and Bolivia. China remains the world's leader not only in production, but also in export and consumption of tungsten products. Tungsten production is gradually increasing outside China because of the rising demand. Meanwhile, its supply by China
7571-579: The cost of providing a given quantity of light by a factor of thirty, compared with the cost at introduction of Edison's lighting system. Consumption of incandescent light bulbs grew rapidly in the US. In 1885, an estimated 300,000 general lighting service lamps were sold, all with carbon filaments. When tungsten filaments were introduced, about 50 million lamp sockets existed in the US. In 1914, 88.5 million lamps were used, (only 15% with carbon filaments), and by 1945, annual sales of lamps were 795 million (more than 5 lamps per person per year). Less than 5% of
7684-404: The density, tungsten is seen as an alternative (albeit more expensive) to lead fishing sinkers . Depleted uranium is also used for these purposes, due to similarly high density. Seventy-five-kg blocks of tungsten were used as "cruise balance mass devices" on the entry vehicle portion of the 2012 Mars Science Laboratory spacecraft. It is an ideal material to use as a dolly for riveting , where
7797-488: The element tungsten is not ferromagnetic (but iron is), when it is present in steel in these proportions, it stabilizes the martensite phase, which has greater ferromagnetism than the ferrite (iron) phase due to its greater resistance to magnetic domain wall motion . Tungsten, usually alloyed with nickel , iron , or cobalt to form heavy alloys, is used in kinetic energy penetrators as an alternative to depleted uranium , in applications where uranium's radioactivity
7910-485: The filament from oxidation . Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment , have low manufacturing costs , and work equally well on either alternating current or direct current . As
8023-615: The filament. General Electric bought the rights to use tantalum filaments and produced them in the US until 1913. From 1898 to around 1905, osmium was also used as a filament in lamps made by Carl Auer von Welsbach . The metal was so expensive that used lamps could be returned for partial credit. It could not be made for 110 V or 220 V so several lamps were wired in series for use on standard voltage circuits. These were primarily sold in Europe. On 13 December 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted
8136-489: The help of Charles Stearn, an expert on vacuum pumps, in 1878, Swan developed a method of processing that avoided the early bulb blackening. This received a British Patent in 1880. On 18 December 1878, a lamp using a slender carbon rod was shown at a meeting of the Newcastle Chemical Society , and Swan gave a working demonstration at their meeting on 17 January 1879. It was also shown to 700 who attended
8249-404: The high quality of its manufacture, it being seldom turned off, and its low wattage. Originally a 60-watt bulb, the light has for many years emitted dim light equivalent to a 4-watt bulb, about the strength of a nightlight. The Centennial Light was originally a 60- watt bulb, but has since dimmed significantly and is now as bright as a 4-watt bulb. The hand-blown, carbon-filament common light bulb
8362-500: The high wear resistance and thermal conductivity of tungsten carbide improves the printing of abrasive filaments. Some string instrument strings incorporates tungsten. Tungsten is used as an absorber on the electron telescope on the Cosmic Ray System of the two Voyager spacecraft . Its density, similar to that of gold, allows tungsten to be used in jewelry as an alternative to gold or platinum . Metallic tungsten
8475-423: The highest boiling point , at 5,930 °C (10,706 °F; 6,203 K). Its density is 19.254 g/cm , comparable with that of uranium and gold , and much higher (about 1.7 times) than that of lead . Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work into metal . However, pure single-crystalline tungsten
8588-515: The highest melting point (3,422 °C, 6,192 °F), lowest vapor pressure (at temperatures above 1,650 °C, 3,000 °F), and the highest tensile strength . Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point. Moreover, tungsten's most stable crystal phase does not exhibit any high-pressure-induced structural transformations for pressures up to at least 364 gigapascals. Tungsten has
8701-518: The inside of lamp bulbs without weakening them. In 1947, he patented a process for coating the inside of lamps with silica . In 1930, Hungarian Imre Bródy filled lamps with krypton gas rather than argon, and designed a process to obtain krypton from air. Production of krypton filled lamps based on his invention started at Ajka in 1937, in a factory co-designed by Polányi and Hungarian-born physicist Egon Orowan . By 1964, improvements in efficiency and production of incandescent lamps had reduced
8814-415: The lamp was lit, with resulting oxygen attacking the filament. In the 1880s, phosphoric anhydride was used in combination with expensive mercury vacuum pumps . However, about 1893, Italian inventor Arturo Malignani [ it ] (1865–1939), who lacked these pumps, discovered that phosphorus vapours did the job of chemically binding the remaining amounts of water and oxygen. In 1896 he patented
8927-480: The less soluble "paratungstate B" anion, H 2 W 12 O 42 . Further acidification produces the very soluble metatungstate anion, H 2 W 12 O 40 , after which equilibrium is reached. The metatungstate ion exists as a symmetric cluster of twelve tungsten- oxygen octahedra known as the Keggin anion. Many other polyoxometalate anions exist as metastable species. The inclusion of
9040-442: The lightbulb. On 4 March 1880, just five months after Edison's light bulb, Alessandro Cruto created his first incandescent lamp. Cruto produced a filament by deposition of graphite on thin platinum filaments, by heating it with an electric current in the presence of gaseous ethyl alcohol . Heating this platinum at high temperatures leaves behind thin filaments of platinum coated with pure graphite. By September 1881 he had achieved
9153-400: The longest-lasting bulb known in existence. In 1976, the fire department moved to Fire Station #6 with the bulb; the bulb socket's cord was severed for fear that unscrewing the bulb could damage it. It was deprived of electricity for only 22 minutes during the transfer, which was made in a specially designed box and with full firetruck escort. An electrician was on hand to install the bulb into
9266-402: The lowest coefficient of thermal expansion of any pure metal. 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. Alloying small quantities of tungsten with steel greatly increases its toughness . Tungsten exists in two major crystalline forms: α and β. The former has
9379-540: The mass necessary for good results can be achieved in a compact bar. High-density alloys of tungsten with nickel, copper or iron are used in high-quality darts (to allow for a smaller diameter and thus tighter groupings) or for artificial flies (tungsten beads allow the fly to sink rapidly). Tungsten is also used as a heavy bolt to lower the rate of fire of the SWD M11/9 sub-machine gun from 1300 RPM to 700 RPM. Tungsten has seen use recently in nozzles for 3D printing ;
9492-431: The metal matrix in place of cobalt because it takes a higher luster when polished. Sometimes manufacturers or retailers refer to tungsten carbide as a metal, but it is a ceramic . Because of tungsten carbide's hardness, rings made of this material are extremely abrasion resistant, and will hold a burnished finish longer than rings made of metallic tungsten. Tungsten carbide rings are brittle, however, and may crack under
9605-538: The metalworking, woodworking, mining , petroleum and construction industries. Carbide tooling is actually a ceramic/metal composite, where metallic cobalt acts as a binding (matrix) material to hold the WC particles in place. This type of industrial use accounts for about 60% of current tungsten consumption. The jewelry industry makes rings of sintered tungsten carbide , tungsten carbide/metal composites, and also metallic tungsten. WC/metal composite rings use nickel as
9718-483: The most stable being W ( t 1/2 6.4 minutes). Tungsten is a mostly non-reactive element: it does not react with water, is immune to attack by most acids and bases, and does not react with oxygen or air at room temperature. At elevated temperatures (i.e., when red-hot) it reacts with oxygen to form the trioxide compound tungsten(VI), WO 3 . It will, however, react directly with fluorine (F 2 ) at room temperature to form tungsten(VI) fluoride (WF 6 ),
9831-412: The most stable of which are W with a half-life of 121.2 days, W with a half-life of 75.1 days, W with a half-life of 69.4 days, W with a half-life of 21.6 days, and W with a half-life of 23.72 h. All of the remaining radioactive isotopes have half-lives of less than 3 hours, and most of these have half-lives below 8 minutes. Tungsten also has 11 meta states , with
9944-543: The museum of the Château de Blois . In 1859, Moses G. Farmer built an electric incandescent light bulb using a platinum filament. Thomas Edison later saw one of these bulbs in a shop in Boston, and asked Farmer for advice on the electric light business. In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in
10057-721: The name Georg Agricola used for the mineral in 1546, which translates into English as ' wolf's froth ' and is a reference to the large amounts of tin consumed by the mineral during its extraction, as though the mineral devoured it like a wolf. This naming follows a tradition of colorful names miners from the Ore Mountains would give various minerals, out of a superstition that certain ones that looked as if they contained then-known valuable metals but when extracted were somehow "hexed". Cobalt (cf. Kobold ), pitchblende (cf. German blenden for ' to blind, to deceive ' ) and nickel (cf. "Old Nick") derive their names from
10170-404: The new fire station's emergency generator. Ripley's Believe It Or Not stated that the short delay would not mar the bulb's continuous burning record. Since that move, the bulb has run continuously on an uninterruptible power supply ; previously it had only been off the grid for short periods of time (e.g. a week in 1937 for a renovation and the odd power outage). In 2001, the bulb's 100th birthday
10283-426: The pervasiveness of the chromium(III) compounds. The highest oxidation state is seen in tungsten(VI) oxide (WO 3 ). Tungsten(VI) oxide is soluble in aqueous base , forming tungstate (WO 4 ). This oxyanion condenses at lower pH values, forming polyoxotungstates . The broad range of oxidation states of tungsten is reflected in its various chlorides: Organotungsten compounds are numerous and also span
10396-619: The physical strength of the catalyst and extends catalyst life. Tungsten containing catalysts are promising for epoxidation, oxidation, and hydrogenolysis reactions. Tungsten heteropoly acids are key component of multifunctional catalysts. Tungstates can be used as photocatalyst, while the tungsten sulfide as electrocatalyst. Applications requiring its high density include weights, counterweights , ballast keels for yachts, tail ballast for commercial aircraft, rotor weights for civil and military helicopters, and as ballast in race cars for NASCAR and Formula One . Being slightly less than twice
10509-412: The power consumed by a typical incandescent light bulb is converted into visible light, with most of the rest being emitted as invisible infrared radiation. Light bulbs are rated by their luminous efficacy , which is the ratio of the amount of visible light emitted ( luminous flux ) to the electrical power consumed. Luminous efficacy is measured in lumens per watt (lm/W). The luminous efficiency of
10622-402: The remaining major use being in alloys and steels. Less than 10% is used in other chemical compounds . Because of the high ductile-brittle transition temperature of tungsten, its products are conventionally manufactured through powder metallurgy , spark plasma sintering , chemical vapor deposition , hot isostatic pressing , and thermoplastic routes. A more flexible manufacturing alternative
10735-1044: The same miners' idiom. Tungsten has thus far not been found in nature in its pure form. Instead, tungsten is found mainly in the minerals wolframite and scheelite . Wolframite is iron – manganese tungstate (Fe,Mn)WO 4 , a solid solution of the two minerals ferberite (FeWO 4 ) and hübnerite (MnWO 4 ), while scheelite is calcium tungstate (CaWO 4 ). Other tungsten minerals range in their level of abundance from moderate to very rare, and have almost no economic value. Tungsten forms chemical compounds in oxidation states from -II to VI. Higher oxidation states, always as oxides, are relevant to its terrestrial occurrence and its biological roles, mid-level oxidation states are often associated with metal clusters , and very low oxidation states are typically associated with CO complexes . The chemistries of tungsten and molybdenum show strong similarities to each other, as well as contrasts with their lighter congener, chromium . The relative rarity of tungsten(III), for example, contrasts with
10848-615: The subject of many TV shows and news reports along with at least four books, and has its own website. The handmade lightbulb was originally manufactured by the Shelby Electric Company of Shelby, Ohio , towards the end of the 1890s and donated to the Livermore-Pleasanton Fire Department in 1901. It has been relocated several times since and remains in the care of the fire department to this day. The bulb's longevity has been attributed to
10961-471: The tens of kilowatts. Therefore, they were only practical for lighting large areas, so researchers continued to search for a way to make lamps suitable for home use. Over the first three-quarters of the 19th century, many experimenters worked with various combinations of platinum or iridium wires, carbon rods, and evacuated or semi-evacuated enclosures. Many of these devices were demonstrated and some were patented. In 1835, James Bowman Lindsay demonstrated
11074-577: The time, machinery to mass-produce coiled coil filaments did not exist. Hakunetsusha developed a method to mass-produce coiled coil filaments by 1936. Between 1924 and the outbreak of the Second World War, the Phoebus cartel attempted to fix prices and sales quotas for bulb manufacturers outside of North America. In 1925, Marvin Pipkin , an American chemist, patented a process for frosting
11187-441: The tungsten allows the welding rod to withstand the high temperatures of the arc welding environment. Quenched (martensitic) tungsten steel (approx. 5.5% to 7.0% W with 0.5% to 0.7% C) was used for making hard permanent magnets, due to its high remanence and coercivity , as noted by John Hopkinson (1849–1898) as early as 1886. The magnetic properties of a metal or an alloy are very sensitive to microstructure. For example, while
11300-445: The web series 17776 . 37°40′48″N 121°44′22″W / 37.68000°N 121.73944°W / 37.68000; -121.73944 Incandescent light bulb An incandescent light bulb , incandescent lamp or incandescent light globe is an electric light with a filament that is heated until it glows . The filament is enclosed in a glass bulb that is either evacuated or filled with inert gas to protect
11413-419: Was a British physicist and chemist. In 1850, he began working with carbonized paper filaments in an evacuated glass bulb. By 1860, he was able to demonstrate a working device but the lack of a good vacuum and an adequate supply of electricity resulted in a short lifetime for the bulb and an inefficient source of light. By the mid-1870s better pumps had become available, and Swan returned to his experiments. With
11526-462: Was a small component in his system of electric lighting, and no more critical to its effective functioning than the Edison Jumbo generator , the Edison main and feeder, and the parallel-distribution system. Other inventors with generators and incandescent lamps, and with comparable ingenuity and excellence, have long been forgotten because their creators did not preside over their introduction in
11639-404: Was celebrated with a community barbecue and live music. On the evening of May 20, 2013, the general public witnessed, through a dedicated webcam , that the bulb had apparently burned out. The next morning, an electrician was called in to confirm its status. It was determined that the bulb had not burned out when the dedicated power supply was bypassed, using an extension cord . The power supply
11752-588: Was found to have been faulty. Approximately 9 hours and 45 minutes had passed before the light was reestablished. The bulb is cared for by the Centennial Light Bulb Committee, a partnership of the Livermore-Pleasanton Fire Department, Livermore Heritage Guild, Lawrence Livermore National Laboratories, and Sandia National Laboratories. The Livermore-Pleasanton Fire Department plans to house and maintain
11865-497: Was granted the first patent for an incandescent lamp, with a design using platinum wires contained within a vacuum bulb. He also used carbon. In 1845, American John W. Starr patented an incandescent light bulb using carbon filaments. His invention was never produced commercially. In 1851, Jean Eugène Robert-Houdin publicly demonstrated incandescent light bulbs on his estate in Blois, France. His light bulbs are on display in
11978-490: Was identical to tungstic acid. Later that year, at the Royal Basque Society in the town of Bergara , Spain, the brothers succeeded in isolating tungsten by reduction of this acid with charcoal , and they are credited with the discovery of the element (they called it "wolfram" or "volfram"). The strategic value of tungsten came to notice in the early 20th century. British authorities acted in 1912 to free
12091-610: Was invented by Adolphe Chaillet , a French engineer who filed a patent for this socket technology. It was manufactured in Shelby, Ohio , by the Shelby Electric Company in the late 1890s; many just like it still exist and can be found functioning. According to Zylpha Bernal Beck, the bulb was donated to the Fire Department by her father, Dennis Bernal, in 1901. Bernal owned the Livermore Power and Water Company and donated
12204-507: Was lit by Joseph Swan's incandescent lamp on 3 February 1879. Thomas Edison began serious research into developing a practical incandescent lamp in 1878. Edison filed his first patent application for "Improvement in Electric Lights" on 14 October 1878. After many experiments, first with carbon in the early 1880s and then with platinum and other metals, in the end Edison returned to a carbon filament. The first successful test
12317-585: Was long thought to be non-radioactive, but Bi (its longest lived isotope) actually decays with a half life of 2.01 × 10 years or about a factor 10 slower than W . However, due to naturally occurring bismuth being 100% Bi , its specific activity is actually higher than that of natural tungsten at 3 milli-becquerel per kilogram. The other naturally occurring isotopes of tungsten have not been observed to decay, constraining their half-lives to be at least 4 × 10 years . Another 34 artificial radioisotopes of tungsten have been characterized,
12430-597: Was off for approximately one week. Its unusual longevity was first noticed in 1972 by reporter Mike Dunstan. After weeks of interviewing people who had lived in Livermore all their lives, he wrote "Light Bulb May Be World's Oldest", published in the Tri-Valley Herald . Dunstan contacted the Guinness Book of World Records , Ripley's Believe It or Not , and General Electric , who all confirmed it as
12543-448: Was on 22 October 1879, and lasted 13.5 hours. Edison continued to improve this design and by 4 November 1879, filed for a US patent for an electric lamp using "a carbon filament or strip coiled and connected ... to platina contact wires." Although the patent described several ways of creating the carbon filament including using "cotton and linen thread, wood splints, papers coiled in various ways," Edison and his team later discovered that
12656-560: Was the first in the world to be lit by a lightbulb. In the early 1880s he had started his company. In 1881, the Savoy Theatre in the City of Westminster , London was lit by Swan incandescent lightbulbs, which was the first theatre, and the first public building in the world, to be lit entirely by electricity. The first street in the world to be lit by an incandescent lightbulb was Mosley Street, Newcastle upon Tyne , United Kingdom . It
12769-492: Was tungsten. Lodygin invented a process where rare metals such as tungsten can be chemically treated and heat-vaporized onto an electrically heated thread-like wire (platinum, carbon, gold) acting as a temporary base or skeletal form. (US patent 575,002). Lodygin later sold the patent rights to GE. In 1902, Siemens developed a tantalum lamp filament that was more efficient than even graphitized carbon filaments since they could operate at higher temperature. Since tantalum metal has
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