It is usually processed by sintering and is a frequent additive as grain growth inhibitor in cemented carbides.

This means that micrometre-sized precipitates of NbC are virtually insoluble in steels at all processing temperatures and their location at grain boundaries helps prevent excessive grain growth in these steels.

This is of enormous benefit, and the cornerstone of microalloyed steels, because it is their uniform, very fine grain size that ensures both toughness and strength.

The only commonly occurring compound with a lower solubility and hence, greater potential for restricting the grain growth of steels is titanium nitride.

Niobocarbide - the naturally occurring form of niobium carbide - shall be regarded as an extremely rare mineral.