This element is no longer available.
Niobium is a rare, soft, malleable, ductile, grey-white metal. It has a body-centred cubic crystalline structure and in its physical and chemical properties it resembles tantalum. It must be placed in a protective atmosphere when processed at even moderate temperatures because it tends to react with oxygen, carbon, the halogens, nitrogen, and sulphur. The metal is inert to acids, even to aqua regia at room temperatures, but is attacked by hot, concentrated acids, and especially by alkalis and oxidizing agents.
Niobium is used for the production of high-temperature-resistant alloys and special stainless steels. Small amounts of niobium impart greater strength to other metals, especially those that are exposed to low temperatures. Niobium carbide is used in cutting tools. It is used in stainless steel alloys for nuclear reactors, jets, missiles, cutting tools, pipelines, super magnets and welding rods.
Niobium-tin and niobium-titanium alloys are used as wires for superconducting magnets capable of producing exceedingly strong magnetic fields. Niobium is also used its pure form to make superconducting accelerating structures for particle accelerators. Niobium alloys are used in surgical implants because they do not react with human tissue.