Niobium carbide Crystal

Niobium carbide is a green cubic crystal with a metallic luster. It is a ceramic material and is amongst the hardest technical compounds known. It is an extremely hard refractory material.

Niobium carbide is Halite, Rock Salt structured and crystallizes in the cubic Fm̅3m space group. Nb⁴⁺ is bonded to six equivalent C⁴⁻ atoms to form a mixture of corner and edge-sharing NbC₆ octahedra. The corner-sharing octahedra are not tilted. All Nb-C bond lengths are 2.25 Å. C⁴⁻ is bonded to six equivalent Nb⁴⁺ atoms to form a mixture of corner and edge-sharing CNb₆ octahedra. The corner-sharing octahedra are not tilted.

Niobium carbide powders are used in the parts and coatings that undergo fretting, abrasion, cavitation, and particle erosion such as cutting tools, grinding tools, agricultural tools, and hard-face coatings. Also, niobium carbide powders are used as grain growth inhibitors in steels.