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Niobium was officially adopted as the name of the element in 1949, but the name columbium remains in current use in metallurgy in the United States. It was not until the early 20th century that niobium was first used commercially. Niobium is an important addition to high-strength low-alloy steels.
Niobium-1% zirconium is used in rocketry and in the nuclear industry. It is regarded as a low-strength alloy. [1] [2]C-103, which is 89% Nb, 10% Hf and 1% Ti, is used for the rocket nozzle of the Apollo service module and the Merlin vacuum [3] engines; it is regarded as a medium-strength alloy.
Niobium carbide has a Young's modulus of approximately 452 GPa, and a shear modulus of 182 GPa. [1] It has a Poisson's ratio of 0.227. [1] Niobium carbide is a frequent intentional product in microalloyed steels due to its extremely low solubility product in austenite, the lowest of all the refractory metal carbides. This means that micrometre ...
Niobium–tin is an intermetallic compound of niobium (Nb) and tin (Sn), used industrially as a type-II superconductor. This intermetallic compound has a simple structure: A3B . It is more expensive than niobium–titanium (NbTi), but remains superconducting up to a magnetic flux density of 30 teslas [T] (300,000 G), [ 1 ] compared to a limit ...
Columbite, also called niobite, niobite-tantalite and columbate, with a general chemical formula of (Fe II,Mn II)Nb 2 O 6, is a black mineral group that is an ore of niobium. It has a submetallic luster, a high density, and is a niobate of iron and manganese. Niobite has many applications in areospace, construction and the medical industry.
It has many polymorphic forms all based largely on octahedrally coordinated niobium atoms. [3] [4] The polymorphs are identified with a variety of prefixes.[3] [4] The form most commonly encountered is monoclinic H-Nb 2 O 5, which has a complex structure with a unit cell containing 28 niobium atoms and 70 oxygen, where 27 of the niobium atoms are octahedrally coordinated and one tetrahedrally. [5]
Ferroniobium is an important iron-niobium alloy, with a niobium content of 60-70%. [1] It is the main source for niobium alloying of HSLA steel and covers more than 80% of the worldwide niobium production. The niobium is mined from pyrochlore deposits and is subsequently transformed into the niobium pentoxide Nb 2 O 5.
Niobium-92 is an extinct radionuclide [6] with a half-life of 34.7 million years, decaying predominantly via β + decay. Its abundance relative to the stable 93 Nb in the early Solar System, estimated at 1.7×10 −5 , has been measured to investigate the origin of p-nuclei .