niobium and one part tin was capable of supporting a current density of more than 100,000 amperes per square centimeter in a magnetic field of 8.8 tesla. Despite being brittle and difficult to fabricate, niobium-tin has since proved extremely useful in supermagnets generating magnetic fields as high as 20 teslas. In 1962, Ted Berlincourt and Richard Hake discovered that less brittle alloys of niobium and titanium are suitable for applications up to 10 teslas. Promptly thereafter, commercial production of niobium-titanium supermagnet wire commenced at Westinghouse Electric Corporation and at Wah Chang Corporation. Although niobium-titanium boasts less-impressive superconducting properties than those of niobium-tin, niobium-titanium has, nevertheless, become the most widely used “workhorse” supermagnet material, in large measure a consequence of its very high ductility and ease of fabrication. However, both niobium-tin and niobium-titanium find wide application in MRI medical imagers, bending and focusing magnets for enormous high-energy particle accelerators, and a host of other applications. Conectus, a European consortium for superconductivity, estimated that in 2014, global economic activity, for which superconductivity was indispensable, amounted to about five billion euros, with MRI systems accounting for about 80% of that total. In 1962, Brian Josephson made the important theoretical prediction that a supercurrent can flow between two pieces of superconductor separated by a thin layer of insulator. This phenomenon, now called the Josephson effect, is exploited by superconducting devices such as SQUIDs. It is used in the most accurate available measurements of the magnetic flux quantum h/2e, and thus (coupled with the quantum Hall resistivity) for Planck's constant h. Josephson was awarded the Nobel Prize in Physics for this work in 1973. In 1973 found to have Tc of 23 K, which remained the highest ambient-pressure Tc until the discovery of the cuprate high-temperature superconductors in 1986 (see below). High-temperature superconductors In 1986, J. Georg Bednorz and K. Alex Mueller discovered superconductivity in a lanthanum-based cuprate perovskite material, which had a transition temperature of 35 K (Nobel Prize in Physics, 1987) and was the first of the high-temperature superconductors. It was shortly found (by Ching-Wu Chu) that replacing the lanthanum with yttrium, i.e. making YBCO, raised the critical temperature to 92 K, which was important because liquid nitrogen could then be used as a refrigerant (at atmospheric pressure, the boiling point of nitrogen is 77 K). This is important commercially because liquid nitrogen can be produced cheaply on-site with no raw materials, and