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|Section2= |Section3= |Section4= }} Chromium carbide is a ceramic compound that exists in several different chemical compositions: Cr3C2, Cr7C3,and Cr23C6. At standard conditions it exists as a gray solid. It is extremely hard and corrosion resistant. It is also a refractory compound, which means that it retains its strength at high temperatures as well. These properties make it useful as an additive to metal alloys. When chromium carbide crystals are integrated into the surface of a metal it improves the wear resistance and corrosion resistance of the metal, and maintains these properties at elevated temperatures. The hardest and most commonly used composition for this purpose is Cr3C2. Related minerals include tongbaite〔(Tongbaite: Tongbaite mineral information and data )〕 and (rare) isovite, (Cr,Fe)23C6.〔Generalov ME, Naumov VA, Mokhov AV, Trubkin NV, "Isovite (Cr,Fe)23C6 - a new mineral from the gold-platinum bearing placers of the Urals", Zapiski Vserossiyskogo mineralogicheskogo obshchestva, vol. 127, pp.26-37, 1998.〕 ==Properties== There are three different crystal structures for chromium carbide corresponding to the three different chemical compositions. Cr23C6 has a cubic crystal structure and a Vickers hardness of 976 kg/mm2. Cr7C3 has a hexagonal crystal structure and a microhardness of 1336 kg/mm2.〔 Cr3C2 is the most durable of the three compositions, and has an orthorhombic crystal structure with a microhardness of 2280 kg/mm2.〔 For this reason Cr3C2 is the primary form of chromium carbide used in surface treatment. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Chromium carbide」の詳細全文を読む スポンサード リンク
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