| 摘要 |
PURPOSE:To provide a large capacity and compact superconductor by heightening critical current density by applying bending in the superconductor formed by aggregating a plurality of multiconductor superconducting strands covered with metal. CONSTITUTION:Oxide and carbonate are mixed together so as to have the composition of Bi:Pb:Sr:Ca:Cu=1.8:0.3:2.0:2.0 : 3.0, and heat treatment is performed, and powder mainly composed of a 2212 phase and a non-superconducting phase is prepared, and after it is filled in a silver pipe, wire drawing work is performed, and multiconductor tape wire conductor layers A, B and C are formed. Heat treatment is performed twice on these conductor wire rods, and the obtained tape-shaped superconducting multiconductor wire rods are collected on a spiral pipe having, for example, a length of 1.4m, an outside diameter of 19mmphi, a thickness of 0.3mm, a groove depth of 2mm and a pitch of 4mm. Before these are aggregated, a silver tape having a thickness of 50mum is wound in a spiral shape round a firmer, and a groove is covered. Next, a winding pitch of the conductor A, B and C wire rods is set, for example, at 250mm, and seventy five pieces are wound in a spiral shape, and the coil direction is reversed with every conductor A, B and C layer. When various-sized bending is applied, a critical current value is improved. |
