[en] This book contains papers presented at a symposium on developments in applied superconductivity. Topics covered include: new superconductors and proposals for their applications, fabrications of superconductors, properties of superconductors, and superconducting magnet technology

[en] This paper reports the results of metal powder such as gold or silver mixed into the Y-Ba-Cu-O system for the purpose of suppressing non-superconducting phase formation in the grain boundary and for filling pores in the YBa₂Cu₃O_7-x sintered bulk. Critical current densities (Jc) appreciably increased by the metal mixing. Especially, 5wt% Au mixing, increased Jc about 4 times larger than that for YBa₂Cu_3-O_7-x without Au. Tc_zero decrease with applying a magnetic field was also suppressed by the metal mixing

[en] The size of the plasma of the next generation of tokamak experiments require superconducting toroidal and poloidal magnet systems. In all tokamak designs around the world field levels needed will be about 12 T. Therefore A 15 (Nb₃Sn) superconductor technology is envisaged for this application. As a typical example for a development program the magnet technology program of the European community is described toward the superconducting magnet system for the Next European Torus (NET)

[en] The development of high J_c microstructures in Nb46.5 wt. % Ti under standard processing techniques is reviewed. Microstructures of alloys of higher Ti content given the same processing are shown to be significantly different. The effect of composition on precipitate morphology has recently been found to be quantifiable, predictable and controllable. The implications of these results in terms of low field applications is discussed

[en] This paper reports the effects of a Nb₃Sn reaction heat treatment on cryogenic mechanical properties of Cr-Ni austenitic steels investigated at low temperatures. Degradation of mechanical properties due to the heat treatment was observed. Their properties were closely connected to grain boundary precipitates and austenitic stability

[en] Raman spectra have been measured on YBa₂Cu₃O_7-δ (YBCO) samples which contain various amount of oxygen deficiency and various substitutional metal atoms. It is found that the 502 cm^-1 mode, which is assigned to the stretching vibration of the oxygen atoms in the BaO layers in the z- direction, shifts downwards monotonically with decreasing the oxygen content 7 - δ. This mode also shifts downwards when a part of the Cu atoms are replaced by Fe, Co, Ga and Al. These results are discussed in relation to the structural change around the Cu ions and around the substitutional sites of dopant metals in YBCO

[en] Characteristics of 10 m-long Nb₃Sn superconducting power transmission cables are discussed. Cables are designed to be suitable for the power of 1 to 3 GW class and assembled using Nb₃Sn superconducting tapes. Current tests of those cables are carried out cooled with liquid or supercritical helium. Details of cable design and experimental method are also described. Cable conductors are consisted of two layers of helically wound tapes, one for transport current and another for shielding. The latest cable N is designed to suppress the stress inside the cable caused by thermal contraction, with a compromise between ideal design and restriction of cable assembly. The results of its current tests are also described, which proved the validity of the new design method

[en] Thin films of Bi-Sr-Ca-Cu-O and Bi-Pb-Sr-Ca-Cu-O superconductor were synthesized by a laser ablation method and also by a multi-target successive deposition technique. The Pb doping decreased the melting temperature, making the formation of high Tc phase much easier. This effect of Pb doping is investigated in detail

[en] The authors have prepared thin films of Y-Ba-Cu-O on the cleaved surface of MgO in an argon-oxygen atmosphere by rf sputtering the rf magnetron sputtering using targets consisting of Y-Ba-Cu-O powder. Resputtering effects were shown in rf-sputtered films. The composition of films is very different from that of targets. Ba and Cu contents are appreciably reduced. However, such resputtering effects could be considerably reduced for films prepared by rf magnetron sputtering. Films deposited without heating MgO substrates were amorphous. After heat treatments of 1 hour at 850-030 degrees C oxygen gas flow, these films exhibit superconductivity. The maximum transition temperature is as high as 80 K. Relations between deposition conditions and transition temperature for as-deposited superconducting films are discussed

[en] This paper reports how, through the design study on multifilamentary superconductors for superconducting generator equipped with rotational field windings, development items were extracted for both NbTi and Nb₃Sn superconductors, The viewpoint to realize the practical rotational machine was insisted in accordance with the operational requirement for the superconducting generator