![]() Finely powdered WC oxidizes readily in hydrogen peroxide aqueous solutions. It reacts with fluorine gas at room temperature and chlorine above 400 ☌ (673 K) and is unreactive to dry HĢ up to its melting point. It is resistant to acids and is only attacked by hydrofluoric acid/ nitric acid (HF/ HNOģ) mixtures above room temperature. The meta-stable nature of this compound results in reduced high temperature stability.Īt high temperatures WC decomposes to tungsten and carbon and this can occur during high-temperature thermal spray, e.g., in high velocity oxygen fuel (HVOF) and high energy plasma (HEP) methods. The fine microstructure of this phase provides high hardness (2800-3500 HV) combined with good toughness when compared with other tungsten carbide compounds. This process causes macrocrystalline WC particles to spheroidize and results in the non-stoichiometric high temperature phase WCġ-x existing in a meta-stable form at room temperature. Īnother meta-stable compound of tungsten and carbon can be created by heating the WC phase to high temperatures using plasma, then quenching in inert gas (plasma spheroidization). Both compounds may be present in coatings and the proportions can depend on the coating method. There are two well-characterized compounds of tungsten and carbon, WC and tungsten semicarbide, WĢC. reacting tungsten hexafluoride with hydrogen (as reducing agent) and methanol (as source of carbon) at 350 ☌ (623 K).reacting tungsten hexachloride with hydrogen (as a reducing agent) and methane (as the source of carbon) at 670 ☌ (943 K).Chemical vapor deposition methods that have been investigated include: ![]() WC can also be produced by heating WO 3 with graphite: directly at 900 ☌ or in hydrogen at 670 ☌ following by carburization in argon at 1,000 ☌. Other methods include a lower temperature fluid bed process that reacts either tungsten metal or blue WO Tungsten carbide is prepared by reaction of tungsten metal and carbon at 1,400–2,000 ☌. Tungsten is Swedish for "heavy stone".Ĭolloquially among workers in various industries (such as machining), tungsten carbide is often simply called carbide. Historically referred to as Wolfram, Wolf Rahm, wolframite ore was then later carburized and cemented with a binder creating a composite now called "tungsten carbide". It is comparable with corundum (α- Alģ) in hardness and can be polished and finished only with abrasives of superior hardness such as cubic boron nitride and diamond powder, wheels and compounds. Tungsten carbide is approximately twice as stiff as steel, with a Young's modulus of approximately 530–700 GPa, and is double the density of steel-nearly the same as gold. 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. Tungsten carbide ( chemical formula: WC) is a chemical compound (specifically, a carbide) containing equal parts of tungsten and carbon atoms. ![]()
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