Vanadium carbides

Vanadium carbide only used in small quantities as a particle growth inhibitor in WC-Co alloys 

Vanadium carbide is manufactured by the carburization of pure vanadium pentoxide (mostly produced from ammonium vanadate) in vacuum at 1700°C. Vanadium carbide exhibits a high hardness, but its brittleness prevents its wide utilization in cemented carbides. In WC-Co alloys, it is added in quantities of 1% by weight as a particle growth inhibitor. 

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Carbon Reduction. The production of ferrovanadium by reduction of vanadium concentrates with carbon has been supplanted by other methods. An important development has been the use of vanadium carbide as a replacement for ferrovanadium as the vanadium additive in steelmaking. A... 

The first carbonitride alloys based on Ti(C,N)—Ni—Mo were iatroduced ia 1970 foUowed by (Ti, Mo)(C,N)-based compositions having fine microstmctures that provided a balance of wear resistance and toughness (4). Continued research on the titanium carbonitride alloys, often called TiC—TiN cermets, ia the 1980s led to the developmeat of complex cermets having a variety of additives such as molybdeaum carbide(2 l) [12069-89-5] M02C, TaC, NbC, zirconium carbide [12020-14-3], ZrC, hafnium carbide [12069-85-1], HfC, WC, vanadium carbide [12070-10-9], VC, chromium carbide (3 2)... 

Vanadium Carbide. Vanadium pentoxide [1314-62-17, V2O5, or vanadium trioxide [1314-34-7] VO3, are the most satisfactory oxides for the preparation of VC. Vanadium pentoxide is best prepared by igniting chemically pure ammonium vanadate [7803-55-6] NH VO, in the presence of moist oxygen to avoid reaction with nitrogen V2O3 is obtained by reduction of V2O3 with hydrogen (see Vanadium compounds). 

Vanadium carbide, VC, deposited from the chloride and methane. 

A striking example of this behavior was described95 for vanadium carbide VC. 

Vanadium carbide (VC) is used to alloy iron to produce high-speed, high-temperature cutting tools for cutting metals and other hard substances. 

The vanadium tetrachloride distils over and is purified from any ferric chloride present either by distillation or by extraction of the product with carbon tetrachloride, in which only the vanadium halide is soluble.2 Sulphuryl chloride, thionyl chloride, sulphur monochloride, and phosgene can all be used in the last reaction instead of chlorine, and the ferrovanadium also can be substituted by vanadium carbide, V4C3,3 nitride, VN,4 subsilicide, V2Si,5 disilicide, VSi2,8 or pentoxide.7... 

Copper Metavanadate.—Addition of copper sulphate solution to sodium metavanadate throws down a precipitate which consists mainly of copper metavanadate, which is light yellow. The precipitate may, however, be green or blue, because its composition varies considerably. Copper metavanadate can also be produced eleetrolytically. On being fused at a high temperature in a graphite crucible it forms copper and vanadium carbide.10... 

Kumashiro Y., Sakuma E., 1980, The Vickers micro-hardness of non-stoichiometric niobium carbide and vanadium carbide single crystals up to 1500°C, J. Mater. Sci., 15, 1321-1324. 

Special carbide tools also will often contain various percentages of titanium, tantalum, niobium icolumbium). and hafnium carbides, along witii die tungsten carbide. Chromium and vanadium carbides are also added to produce special, fine-grain-size grades of cemented tungsten carbide-cobalt materials. See Fig. 1. 

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