What Is Titanium Carbide?
Titanium carbide (TiC) is a face-centered cubic lattice crystal, part of the NaCl-type structure, where metal and carbon atoms are alternately arranged. It has a molar mass of 59.9 g/mol, melts at 3,170℃, and has a density of 4.9 g/cm3. Identified by CAS number 12070-08-5, titanium carbide appears as a black powder at room temperature. Its production, which began in the 20th century, was aimed at replacing expensive tungsten in filaments.
Naturally occurring as khamrabaevite [(Ti,V,Fe)C], it is a rare mineral with crystals typically ranging from 0.1mm to 0.3mm in size.
Properties of Titanium Carbide
With its insolubility in water, solubility in nitric acid and aqua regia, high electrical conductivity, and a Vickers hardness of around 3,200, titanium carbide is notable for its exceptional properties. It is produced through various industrial methods, including vacuum carbonization and plasma processes, among others. Recent research has shown that a titanium-to-carbon ratio of 2:1 allows for the creation of high-strength sintered bodies at around 1500℃ in just minutes.
Uses of Titanium Carbide
1. Cutting Tools
Due to its extreme hardness and high melting point, titanium carbide is integral to cutting tools. It is typically combined with cobalt, nickel, and molybdenum, providing a cost-effective alternative to tungsten-based cemented carbides. Its addition to tungsten carbide enhances wear and oxidation resistance, making it ideal for high-speed steel machining. Despite its hardness, its brittleness under impact and rapid cooling requires careful handling.
2. Coating Materials
As a coating, titanium carbide offers metal-like surface characteristics, enhancing the wear resistance of precision parts and instruments, including machine components and watch elements. Its application in arc electrolysis and as a welding aid for aluminum alloys showcases its versatility. Known for its low friction coefficient and excellent heat resistance among the various ceramic coatings, it is a preferred material for high-temperature component coatings.
3. Other Applications
Beyond coatings, titanium carbide is utilized in the mold-release processes for steel and resins, benefiting press molding, cold forging, and plastic molding. Its hypoallergenic and lightweight nature also makes it a popular choice for jewelry, such as necklaces.