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Tantalum carbide is widely used as sintering additive in ultra-high temperature ceramics (UHTCs) or as a ceramic reinforcement in high-entropy alloys (HEAs) due to its excellent physical properties in melting point, hardness, elastic modulus, thermal conductivity, thermal shock resistance, and chemical stability, which makes it a desirable ...
Tantalum carbide, TaC, like the more commonly used tungsten carbide, is a hard ceramic that is used in cutting tools. Tantalum(III) nitride is used as a thin film insulator in some microelectronic fabrication processes.
Tantalcarbide is a rare mineral of tantalum carbide with formula TaC. With a molecular weight of 192.96 g/mol, its primary constituents are tantalum (93.78%) and carbon (6.22%), and has an isometric crystal system. [2] It generally exhibits a bronze or brown to yellow color. On the Mohs hardness scale it registers as a 6–7. [3]
The first cemented carbide developed was tungsten carbide (introduced in 1927) which uses tungsten carbide particles held together by a cobalt metal binder. Since then, other cemented carbides have been developed, such as titanium carbide, which is better suited for cutting steel, and tantalum carbide, which is tougher than tungsten carbide. [1]
Hafnium carbide (Hf C) is a chemical compound of hafnium and carbon.Previously the material was estimated to have a melting point of about 3,900 °C. [2] More recent tests have been able to conclusively prove that the substance has an even higher melting point of 3,958 °C exceeding those of tantalum carbide and tantalum hafnium carbide which were both previously estimated to be higher. [3]
Chlorination of hafnium carbide above 250 °C. [9] Hafnium(IV) bromide (HfBr 4) is a colourless, diamagnetic moisture sensitive solid that sublimes in vacuum. [10] It adopts a structure very similar to that of zirconium tetrabromide, featuring tetrahedral Hf centers, in contrast to the polymeric nature of hafnium tetrachloride. [11]
Methanides are a subset of carbides distinguished by their tendency to decompose in water producing methane. Three examples are aluminium carbide Al 4 C 3, magnesium carbide Mg 2 C [9] and beryllium carbide Be 2 C. Transition metal carbides are not saline: their reaction with water is very slow and is usually neglected.
Figure 1. An UHTC strake composed of three different sections with different UHTC compositions. [4]Beginning in the early 1960s, demand for high-temperature materials by the nascent aerospace industry prompted the United States Air Force Materials Laboratory to begin funding the development of a new class of materials that could withstand the environment of proposed hypersonic vehicles such as ...