Search results
Results from the WOW.Com Content Network
Tantalum carbides (TaC) form a family of binary chemical compounds of tantalum and carbon with the empirical formula TaC x, where x usually varies between 0.4 and 1. They are extremely hard , brittle, refractory ceramic materials with metallic electrical conductivity .
Because of the complexity of X-ray lenses, it is difficult to form an image of the crystal being diffracted, and hence phase information is lost. Fortunately, electron microscopes can resolve atomic structure in real space and the crystallographic structure factor phase information can be experimentally determined from an image's Fourier transform.
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 coefficient of thermal expansion of cemented tungsten carbide is found to vary with the amount of cobalt used as a metal binder. For 5.9% cobalt samples, a coefficient of 4.4 μm/m·K was measured, whereas 13% cobalt samples have a coefficient of around 5.0 μm/m·K.
Tantalum-Carbon Bond. Organotantalum chemistry is the chemistry of chemical compounds containing a carbon-to-tantalum chemical bond. A wide variety of compound have been reported, initially with cyclopentadienyl and CO ligands. Oxidation states vary from Ta(V) to Ta(-I).
The beta phase is metastable and converts to the alpha phase upon heating to 750–775 °C. Bulk tantalum is almost entirely alpha phase, and the beta phase usually exists as thin films [ 76 ] obtained by magnetron sputtering , chemical vapor deposition or electrochemical deposition from a eutectic molten salt solution.
Tantalum hafnium carbide is a refractory chemical compound with a general formula Ta x Hf y C x+y, which can be considered as a solid solution of tantalum carbide and hafnium carbide. It was originally thought to have the highest melting of any known substance but new research has proven that hafnium carbonitride has a higher melting point.
Tantalum is a chemical element; it has symbol Ta and atomic number 73. It is named after Tantalus, a figure in Greek mythology. [11] Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant.