Stellites are used in bearings, pistons and valve seats, as well as in applications that require materials with tough wear-resistant properties. When mixed with heavy concentrations of tungsten, molybdenum, tantalum and rhenium, the metals nickel, iron or cobalt form superalloys.
Superalloys exhibit several special properties including high temperature tolerance, high corrosion resistance and excellent welding properties. Applications of superalloys include marine vehicles, the turbine blades of aircraft engines, and turbine vanes and blades in stationary power supplies.
The addition of tungsten makes steel stronger. Tungsten is the primary alloy component in steels used for tools and construction. Steel alloys with tungsten are used for cutting and making metal components.
As such, it is important that these steel alloys possess excellent hardness properties over a wide range of temperatures. Tungsten finds many applications in laboratories.
It serves as a reagent in the form of high purity sodium tungstate in biochemical analysis. Because tungsten alloys tend to be strong and flexible, resist wear and corrosion, and conduct electricity well, they are used in different applications, for example, tungsten-steel alloys are used in the production of rocket engine nozzles, which must have good heat resistant properties, super-alloys containing tungsten are used in turbine blades and wear-resistant parts and coatings, while high-density alloys of tungsten with nickel , copper or iron are used in high-quality darts.
Because tungsten has conductive properties and relative chemical inertness, it is also used in electrodes, for instance in electron microscopes. Tungsten's tolerance to intense heat also makes it an ideal material in electronics. For example, tungsten is used as an interconnect material in integrated circuits, between the silicon dioxide dielectric material and transistors. At present, tungsten carbide base hard alloy is the largest consumption field of tungsten, the carbide is a powder metallurgy product that is made of tungsten carbide micron powder and metal binder such as cobalt, nickel, molybdenum in vacuum furnace or hydrogen reduction sintering furnace.
Tungsten carbide base hard alloy is generally can be divided into four types such as tungsten carbide - cobalt - tungsten carbide, titanium carbide - cobalt - tungsten carbide, titanium carbide, tantalum carbide - cobalt, and steel bonded hard alloy, the tungsten carbide base hard alloy is mainly used in the manufacture of cutting tools, mining tools and wire drawing dies, etc.
Tungsten is the highest melting point of all metals, the hardness is very high, so it is often used to produce strong heat and wear-resistant alloy, for example, tungsten, cobalt, chromium, and carbon alloy used to produce high strength and wear-resistant parts such as aviation engine valve, turbine impeller, etc, Tungsten and other refractory metals alloys are used to produce high strength parts such as air rocket engine nozzle.
Because tungsten has high density and high hardness, thus became the ideal material for making high proportion alloy. According to the composition, properties, and uses, the high proportion alloy is divided into W-Ni-Fe, W-Ni-Cu, W-Co, W-WC-Cu, W-Ag, and other major series, this alloy has many properties such as heavy, high strength, radiation absorption ability, thermal conductivity, and the thermal expansion coefficient, good conductive properties, weldability, and good processing, widely used in aerospace, aviation, military, oil drilling, electrical instrumentation, medical and other industries, such as manufacturing contact material balance hammer armor, fin, rudder, and control such as switch, circuit breaker, spot welding electrode, etc.
Tungsten is widely used in the electronics and power industry because of its high plasticity, low evaporation rate, high melting point, and high electron emission ability.
For example, with the high light rate and long service life, so tungsten is widely used in the manufacture of various bulb filament, such as incandescent lamps, halogen lamps, tungsten wire can also be used in the manufacture of electronic tubes direct hot cathode, gate and a variety of electronic instruments by hot cathode heater.
The properties of tungsten make it suitable for use in TIG welding and other similar materials. 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. However in '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.
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 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.
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.
Next week we'll meet the element that was introduced to the world in, its fair to say, a pretty unusual way. 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 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 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. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.
Click here to view videos about Tungsten. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R.
Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets.
Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton.
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