Niobium–titanium (Nb-Ti) is an alloy of niobium and titanium, used industrially as a type II superconductor wire for superconducting magnets, normally as Nb-Ti fibres in an aluminium or copper matrix.
Its critical temperature is about 10 kelvins. [1]
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. [2] [3] 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, 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. [4] Magnet resonance imaging (MRI) systems, most of which use Nb-Ti, accounted for about 80% of the total market value.
A bubble chamber at Argonne National Laboratory has a 4.8-meter-diameter Nb-Ti magnet, which produces a magnetic field of 1.8 tesla. [5]
About 1,000 Nb-Ti SC magnets were used in the 4-mile-long main ring of the Tevatron accelerator at Fermilab. [6] The magnets were wound with 50 tons of copper cables, containing 17 tons of Nb-Ti filaments. [7] They operate at 4.5 K and generate fields of up to 4.5 T.
1999: The Relativistic Heavy Ion Collider uses 1,740 Nb-Ti SC 3.45 T magnets to bend beams in its 3.8 km double storage ring. [8]
In the Large Hadron Collider particle accelerator, the magnets contain 1,200 tonnes of Nb-Ti cable, [9] of which 470 tons are Nb-Ti [10] 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. They were later replaced by non-superconducting magnets.
The experimental fusion reactor ITER uses niobium–titanium for its poloidal field coils. In 2008, a test coil achieved stable operation at 52 kA and 6.4 T. [11]
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 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, Nagoya, and Osaka 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. [12]
Niobium is a chemical element with chemical symbol Nb and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish.
Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic fields are expelled from the material. Any material exhibiting these properties is a superconductor. Unlike an ordinary metallic conductor, whose resistance decreases gradually as its temperature is lowered, even down to near absolute zero, a superconductor has a characteristic critical temperature below which the resistance drops abruptly to zero. An electric current through a loop of superconducting wire can persist indefinitely with no power source.
Some of the technological applications of superconductivity include:
The Tevatron was a circular particle accelerator in the United States, at the Fermi National Accelerator Laboratory, east of Batavia, Illinois, and is the second highest energy particle collider ever built, after the Large Hadron Collider (LHC) of the European Organization for Nuclear Research (CERN) near Geneva, Switzerland. The Tevatron was a synchrotron that accelerated protons and antiprotons in a 6.28 km (3.90 mi) ring to energies of up to 1 TeV, hence its name. The Tevatron was completed in 1983 at a cost of $120 million and significant upgrade investments were made during its active years of 1983–2011.
The Large Hadron Collider (LHC) is the world's largest and highest-energy particle collider. It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and hundreds of universities and laboratories, as well as more than 100 countries. It lies in a tunnel 27 kilometres (17 mi) in circumference and as deep as 175 metres (574 ft) beneath the France–Switzerland border near Geneva.
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 larger electric currents than ordinary wire, creating intense magnetic fields. Superconducting magnets can produce stronger magnetic fields than all but the strongest non-superconducting electromagnets, and large superconducting magnets can be cheaper to operate because no energy is dissipated as heat in the windings. They are used in MRI instruments in hospitals, and in scientific equipment such as NMR spectrometers, mass spectrometers, fusion reactors and particle accelerators. They are also used for levitation, guidance and propulsion in a magnetic levitation (maglev) railway system being constructed in Japan.
The tesla is the unit of magnetic flux density in the International System of Units (SI).
The International Linear Collider (ILC) is a proposed linear particle accelerator. It is planned to have a collision energy of 500 GeV initially, with the possibility for a later upgrade to 1000 GeV (1 TeV). Although early proposed locations for the ILC were Japan, Europe (CERN) and the USA (Fermilab), the Kitakami highland in the Iwate prefecture of northern Japan has been the focus of ILC design efforts since 2013. The Japanese government is willing to contribute half of the costs, according to the coordinator of study for detectors at the ILC.
Superconductivity is the phenomenon of certain materials exhibiting zero electrical resistance and the expulsion of magnetic fields below a characteristic temperature. The history of superconductivity began with Dutch physicist Heike Kamerlingh Onnes's discovery of superconductivity in mercury in 1911. Since then, many other superconducting materials have been discovered and the theory of superconductivity has been developed. These subjects remain active areas of study in the field of condensed matter physics.
The Very Large Hadron Collider (VLHC) was a proposed future hadron collider planned to be located at Fermilab. The VLHC was planned to be located in a 233 kilometres (145 mi) ring, using the Tevatron as an injector. The VLHC would run in two stages, initially the Stage-1 VLHC would have a collision energy of 40 TeV, and a luminosity of at least 1⋅1034 cm−2⋅s−1 (matching or surpassing the LHC design luminosity, however the LHC has now surpassed this).
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), compared to a limit of roughly 15 T for NbTi.
In superconductivity, a type-II superconductor is a superconductor that exhibits an intermediate phase of mixed ordinary and superconducting properties at intermediate temperature and fields above the superconducting phases. It also features the formation of magnetic field vortices with an applied external magnetic field. This occurs above a certain critical field strength Hc1. The vortex density increases with increasing field strength. At a higher critical field Hc2, superconductivity is destroyed. Type-II superconductors do not exhibit a complete Meissner effect.
The High Luminosity Large Hadron Collider is an upgrade to the Large Hadron Collider, operated by the European Organization for Nuclear Research (CERN), located at the French-Swiss border near Geneva. From 2011 to 2020, the project was led by Lucio Rossi. In 2020, the lead role was taken up by Oliver Brüning.
A Rutherford cable is a way of forming a superconducting electrical cable, often used to generate magnetic fields in particle accelerators. The superconducting strands are arranged as a many-stranded helix that has been flattened into a rectangular cable. It can typically only be applied to flexible superconductors that can be drawn into wire such as the niobium-based superconductors used in the Large Hadron Collider. The cable is named after the Rutherford Laboratory where the cable design was developed.
Alexander Shikov, D. Sc. was a Russian materials scientist.
Superconducting wires are electrical wires made of superconductive material. When cooled below their transition temperatures, they have zero electrical resistance. Most commonly, conventional superconductors such as niobium–titanium are used, but high-temperature superconductors such as YBCO are entering the market.
A niobium alloy is one in which the most common element is niobium.
Lucio Rossi is an Italian physicist who is working in the field of superconductivity. He has been working since 2001 at CERN, on leave from the University of Milan, where he directed the Magnets & Superconductors for the LHC project, worth €1.7 billion, half of the machine's entire budget. He was the project leader of the HL-LHC project.
The Future Circular Collider (FCC) is a proposed particle accelerator with an energy significantly above that of previous circular colliders, such as the Super Proton Synchrotron, the Tevatron, and the Large Hadron Collider (LHC). The FCC project is considering three scenarios for collision types: FCC-hh, for hadron-hadron collisions, including proton-proton and heavy ion collisions, FCC-ee, for electron-positron collisions, and FCC-eh, for electron-hadron collisions.
John Kenneth Hulm was a British-American physicist and engineer, known for the development of superconducting materials with applications to high-field superconducting magnets. In 1953 with George F. Hardy he discovered the first A-15 superconducting alloy.
The test coil achieves stable operation at 52 kA and 6.4 Tesla.