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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 .
Tantalum is a chemical element; it has symbol Ta and atomic number 73. Previously known as tantalium, [citation needed] 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.
In the following table, ... 73 Ta tantalum; use: 3290 K: 3017 °C: 5463 °F WEL: ... The bcc phase and the P-T and VT phase diagrams below 2 K".
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.
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 phase diagram shows, in pressure–temperature space, the lines of equilibrium or phase boundaries between the three phases of solid, liquid, and gas. The curves on the phase diagram show the points where the free energy (and other derived properties) becomes non-analytic: their derivatives with respect to the coordinates (temperature and ...
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.
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.