Wikipedia
Tantalum carbides form a family of binary chemical compounds of tantalum and carbon with the empirical formula TaC, where x usually varies between 0.4 and 1. They are extremely hard, brittle, refractory ceramic materials with metallic electrical conductivity. They appear as brown-gray powders which are usually processed by sintering. Being important cermet materials, tantalum carbides are commercially used in tool bits for cutting applications and are sometimes added to tungsten carbide alloys. The melting points of tantalum carbides peak at about 3880 °C depending on the purity and measurement conditions; this value is among the highest for binary compounds. Only tantalum hafnium carbide may have a slightly higher melting point of about 3942 °C, whereas the melting point of hafnium carbide is comparable to that of TaC.
Usage examples of "tantalum carbide".
Doping them with compounds like tantalum carbide makes them into submicron-sized superconducting wires, and packing them with potassium-doped buckyballs achieves the same effect, and if the buckytube is sized properly to fit the buckyball such packing would probably also serve to increase their already phenomenal stiffness and boost their compressive strength as well.