Niobium–titanium (Nb-Ti) is a ductile

alloy An alloy is a mixture of chemical elements of which in most cases at least one is a metal, metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have prop ...

niobium Niobium is a chemical element; it has chemical symbol, symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and Ductility, ductile transition metal. Pure niobium has a Mohs scale of mineral hardness, Mohs h ...

and

titanium Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...

, used industrially as a type II superconductor wire for

superconducting magnet A superconducting magnet is an electromagnet made from coils of superconducting wire. They must be cooled to cryogenic temperatures during operation. In its superconducting state the wire has no electrical resistance and therefore can conduct much ...

s, normally as Nb-Ti fibres in an aluminium or copper matrix. Its

critical temperature Critical or Critically may refer to: *Critical, or critical but stable, medical states **Critical, or intensive care medicine *Critical juncture, a discontinuous change studied in the social sciences. *Critical Software, a company specializing in ...

is about 10 kelvins. The high critical magnetic field and high critical supercurrent density of Nb-Ti was discovered in 1962 at Atomics International by T. G. Berlincourt and R. R. Hake. Nb-Ti alloys are notable for their easy workability and affordability, distinguishing them from other superconducting materials. Nb-Ti alloys have a maximal critical magnetic field of about 15 teslas and, thus, are suitable for fabricating supermagnets capable of generating magnetic fields of up to about 10 teslas. For stronger magnetic fields, higher performance superconductors, such as

niobium–tin 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 ...

, are commonly used, but these are more difficult to fabricate and more expensive to produce. The global superconductivity market was valued at around five billion euros in 2014. Magnet resonance imaging (MRI) systems, most of which use Nb-Ti, accounted for about 80% of the total market value.

Notable uses

Superconducting magnets

bubble chamber A bubble chamber is a vessel filled with a superheated transparent liquid (most often liquid hydrogen) used to detect electrically charged particles moving through it. It was invented in 1952 by Donald A. Glaser, for which he was awarded th ...

Argonne National Laboratory Argonne National Laboratory is a Federally funded research and development centers, federally funded research and development center in Lemont, Illinois, Lemont, Illinois, United States. Founded in 1946, the laboratory is owned by the United Sta ...

has a 4.8-meter-diameter Nb-Ti magnet, which produces a magnetic field of 1.8 tesla. About 1,000 Nb-Ti SC magnets were used in the 4-mile-long main ring of the

Tevatron The Tevatron was a circular particle accelerator (active until 2011) in the United States, at the Fermilab, Fermi National Accelerator Laboratory (called ''Fermilab''), east of Batavia, Illinois, and was the highest energy particle collider unt ...

accelerator at

Fermilab Fermi National Accelerator Laboratory (Fermilab), located in Batavia, Illinois, near Chicago, is a United States Department of Energy United States Department of Energy National Labs, national laboratory specializing in high-energy particle phys ...

. The magnets were wound with 50 tons of copper cables, containing 17 tons of Nb-Ti filaments. They operate at 4.5 K and generate fields of up to 4.5 T. 1999: The

Relativistic Heavy Ion Collider The Relativistic Heavy Ion Collider (RHIC ) is the first and one of only two operating heavy- ion colliders, and the only spin-polarized proton collider ever built. Located at Brookhaven National Laboratory (BNL) in Upton, New York, and used ...

uses 1,740 Nb-Ti SC 3.45 T magnets to bend beams in its 3.8 km double storage ring. In the

Large Hadron Collider The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator. It was built by the CERN, European Organization for Nuclear Research (CERN) between 1998 and 2008, in collaboration with over 10,000 scientists, ...

particle accelerator A particle accelerator is a machine that uses electromagnetic fields to propel electric charge, charged particles to very high speeds and energies to contain them in well-defined particle beam, beams. Small accelerators are used for fundamental ...

, the magnets contain 1,200 tonnes of Nb-Ti cable, of which 470 tons are Nb-Ti and the rest copper, and they are cooled to 1.9 K to allow the safe operation of fields of up to 8.3 T. Niobium–titanium superconducting magnet coils (liquid-helium-cooled) were built to be used in the Alpha Magnetic Spectrometer mission at the

International Space Station The International Space Station (ISS) is a large space station that was Assembly of the International Space Station, assembled and is maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United ...

. They were later replaced by non-superconducting magnets. The experimental

fusion reactor Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. In a fusion process, two lighter atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices ...

ITER ITER (initially the International Thermonuclear Experimental Reactor, ''iter'' meaning "the way" or "the path" in Latin) is an international nuclear fusion research and engineering megaproject aimed at creating energy through a fusion process s ...

uses niobium–titanium for its poloidal field coils. In 2008, a test coil achieved stable operation at 52 kA and 6.4 T. The Wendelstein 7-X stellarator uses Nb-Ti for its magnets, which are cooled to 4 K to create a 3 T field. The

SCMaglev The SCMaglev (superconducting maglev, formerly called the MLU) is a magnetic levitation (maglev) railway system developed by Central Japan Railway Company (JR Central) and the Railway Technical Research Institute. The SCMaglev uses an electrod ...

uses Nb-Ti for the magnets onboard trains. A train using the technology currently holds the train speed world record of 603 km/h. It will be deployed for the Chūō Shinkansen, providing passenger service between

Tokyo Tokyo, officially the Tokyo Metropolis, is the capital of Japan, capital and List of cities in Japan, most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is List of largest cities, one of the most ...

Nagoya is the largest city in the Chūbu region of Japan. It is the list of cities in Japan, fourth-most populous city in Japan, with a population of 2.3million in 2020, and the principal city of the Chūkyō metropolitan area, which is the List of ...

, and

Osaka is a Cities designated by government ordinance of Japan, designated city in the Kansai region of Honshu in Japan. It is the capital of and most populous city in Osaka Prefecture, and the List of cities in Japan, third-most populous city in J ...

at a planned maximum operating speed of 505 km/h. Construction is underway for the Tokyo–Nagoya segment, with a planned opening date of 2027.

Gallery

Cross section of preform superconductor cable.jpg , Cross section of preform superconductor cable 2.jpg , Cross section of preform superconductor cable 3.jpg ,

References

{{DEFAULTSORT:Niobium-titanium Superconductors Niobium alloys Titanium alloys

Notable uses

Superconducting magnets

Gallery

See also

Further reading

References