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Niobium alloyA niobium alloy is one in which the most common element is niobium. Alloys used for the production of other alloysThe most common commercial niobium alloys are ferroniobium and nickel-niobium, produced by thermite reduction of appropriate mixtures of the oxides; these are not usable as engineering materials, but are used as convenient sources of niobium for specialist steels and nickel-based superalloys. Going via an iron-niobium or nickel-niobium alloy avoids problems associated with the high melting point of niobium. Superconducting alloys Niobium-tin and Niobium-titanium are essential alloys for the industrial use of superconductors, since they remain superconducting in high magnetic fields (30 T for Nb3Sn, 15 T for NbTi); there are 1200 tons of NbTi in the magnets of the Large Hadron Collider, whilst Nb3Sn is used in the windings of almost all hospital MRI machines. Aerospace rivetsNiobium-titanium alloy, of the same composition as the superconducting one, is used for rivets in the aerospace industry; it is easier to form than CP titanium, and stronger at elevated (> 300°C) temperatures. Refractory alloysNiobium-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. It is typically produced using gas atomization or plasma atomization techniques.[4] It is particularly used in additive manufacturing (3D printing) and powder metallurgy processes.[5] Due to its corrosion resistance and high thermal efficiency, C103 helps reduce material waste and environmental pollution.[6] High-strength alloys include C-129Y (10% tungsten, 10% hafnium, 0.1% yttrium, balance niobium), Cb-752 (10% tungsten, 2.5% zirconium), and the even higher strength C-3009 (61% niobium, 30% hafnium, 9% tungsten); these can be used at temperatures up to 1650°C with acceptable strength, though are expensive and hard to form. Nb-Hf-Ti is an alloy powder consisting of niobium (Nb), hafnium (Hf), and a small amount of titanium (Ti) provides high strength, ductility, high-temperature stability, and remarkable corrosion resistance.[7] It is used in manufacturing biocompatible implants and devices such as orthopedic implants and dental prosthetics.[8] Niobium alloys in general are inconvenient to weld: both sides of the weld must be protected with a stream of inert gas, because hot niobium will react with oxygen and nitrogen in the air. It is also necessary to take care (e.g. hard chrome-plating of all copper tooling) to avoid copper contamination. References
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