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niobium ni·o·bi·um (nī-ō'bē-əm)
A soft ductile metallic element that is used in steel alloys and superconductors. Atomic number 41; atomic weight 92.906; melting point 2,477°C; boiling point 4,744°C; specific gravity 8.57; valence 2, 3, 5.
A soft, silvery, ductile metallic element that usually occurs in nature together with the element tantalum. It is used to build nuclear reactors, to make steel alloys, and to allow magnets to conduct electricity with almost no resistance. Atomic number 41; atomic weight 92.906; melting point 2,468°C; boiling point 4,927°C; specific gravity 8.57; valence 2, 3, 5. See Periodic Table.
chemical element, refractory metal of Group Vb of the periodic table, used in alloys, tools and dies, and superconductive magnets. Niobium is closely associated with tantalum in ores and in properties.