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Tungsten (also called wolfram) [ 11][ 12] is a chemical element; it has symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783.
Wolfram Crisis. The Wolfram Crisis (Spanish: Crisis del wolframio) was a diplomatic conflict during World War II between Francoist Spain and the Allied powers, which sought to block Spanish exports of tungsten ore to Nazi Germany. "Wolfram" is an alternate name for tungsten, a strategic material used in anti-tank weapons and machine tools.
Wolframite is an iron, manganese, and tungstate mineral with a chemical formula of (Fe,Mn)WO4 that is the intermediate mineral between ferberite ( Fe2+ rich) and hübnerite ( Mn2+ rich). [4] Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite is found in quartz veins and pegmatites associated ...
Not classified as an element until the 1780s, tungsten likely first popped up in German chemistry as ‘Wolfram,’ and Brahe’s medicine were known to have German influence. “Maybe Tycho Brahe ...
Tungsten, also known as wolfram, is a chemical element with the chemical symbol W and atomic number 74. The word tungsten comes from the Swedish language tung sten directly translatable to heavy stone , [ 17 ] though the name is volfram in Swedish to distinguish it from Scheelite , in Swedish alternatively named tungsten .
Tungsten carbide (chemical formula: WC) is a chemical compound (specifically, a carbide) containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering for use in industrial machinery, cutting tools, chisels, abrasives, armor-piercing shells and jewelry.
A halogen lamp (also called tungsten halogen, quartz-halogen, and quartz iodine lamp) is an incandescent lamp consisting of a tungsten filament sealed in a compact transparent envelope that is filled with a mixture of an inert gas and a small amount of a halogen, such as iodine or bromine. The combination of the halogen gas and the tungsten ...
Another delicate issue was the trade in wolfram . Following the invasion of the Soviet Union, Germany became dependent on Portugal and Spain for their wolfram supplies, since it was of particular value in producing war munitions. To maintain her neutrality, Portugal set up a strict export quota system in 1942.