TiC = Titanium Carbide, an extremely hard (Mohs 9-9.5) refractory ceramic material, similar to tungsten carbide. It is commercially used in tool bits cutting tools. It has the appearance of black powder with NaCl-type face centered cubic crystal structure. It is mainly used in preparation of cermets, which are frequently used to machine steel materials at high cutting speed. The resistance to wear, corrosion, and oxidation of a tungsten carbide-cobalt material can be increased by adding 6-30% of titanium carbide to tungsten carbide. This forms a solid solution that is more brittle and susceptible to breakage than the original material. It is usually employed INTERSTITIALLY. VC = Vanadium Carbide, an extremely hard refractory ceramic material. It is commercially used in tool bits cutting tools. It has the appearance of gray metallic powder with cubic crystal structure. Vanadium carbide is chemically stable and has excellent high-temperature property. It can be used as an additive to tungsten carbide to fine the carbide crystals to improve the property of the cermet. Vanadium Carbide can be formed in the (1,1,1) orientation, when formed by R.F. Magnetron Sputtering. Although Vanadium Carbide is a very thermodynamically stable ceramic, V2C is energy favorable to exist at temperatures above 900oC. It is usually employed INTERSTITIALLY. WC = Tungsten Carbide is high melting, 2,870 °C (5,200 °F), extremely hard 8.5–9.0 Mohs scale at 22 GPa Vickers hardness with low electrical resistivity (1.7–2.2x10-7 ohm-m), comparable with metals (e.g. vanadium 1.99x10-7 ohm-m). There are two well characterized compounds of tungsten and carbon, WC and W2C. Both compounds may be present in coatings, and the proportions can depend on the coating method. It is usually employed as a COMPOUND. SiC = Silicon Carbide is a compound of silicon and carbon bonded together to form ceramics, but it also occurs in nature as the extremely rare mineral moissanite. Most often it is used as an abrasive, and more recently as a semiconductor and diamond simulant of gem quality. It is usually employed as a COMPOUND.