Superconducting materials

The properties and production technology are described of various superconducting materials. Until recently the most widely used was the NbTi alloy multifilamentary conductor. Currently, the use of Nb3Sn and V3Ga strips and multifilamentary conductors is expanding. The advantage of these materials as compared with NbTi is their higher critical temperature and higher value of the critical magnetic field. Even more favourable superconducting properties are manifested by Nb3Ge which is the sole known material which is superconducting at liquid hydrogen temperature. Its preparation is, however, extremely difficult. The assumed trends of the further development of superconducting materials are indicated. (Ha)