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The effects of mechanical fatigue on the electrical transport properties of Y-Ba-Cu-O/Hastelloy-C coated conductors at 77 K are examined. The analysis of the fatigue strength and ductility behaviors has shown that the fatigue strength exponent is within the values found for metals, but both the fatigue ductility coefficient and exponent has shown that the material tested is brittle.

A new approach is described for the magnet fabrication, react, wind and sinter (RWS) of [Bi.sub.2][Sr.sub.2]Ca[Cu.sub.2][O.sub.x] (Bi2212) magnets. The results have shown that split melt processing and RWS magnet fabrication are viable methods for Bi2212 conductors and magnets.

High temperature superconductor (HTS) based conductor and magnet technologies are analyzed. HTS conductors have shown the ability to carry very large critical current densities at magnetic fields of 45 T and two insert coil demonstrations have surpassed the 25 T barrier.

The performance of alternating current (ac) loss and quench behavior measurements on a Y[Ba.sub.2][Cu.sub.3][O.sub.7] coated conductor at 45 K is discussed. Findings reveal similar dc and ac quench behavior.

The progress in the development of multifilament Bi-2212/Ag wires for magnet applications is discussed. Findings reveal the achievement of the highest critical current density of 1580 A/[mm.sup.2] at 4.2 K, 0T and 420 A/[mm.sup.2] at 4.2 K, 31 T in 0.81 mm wire.

A new versatile total AC loss and stability characterization facility for various high temperature superconducting materials at different temperatures has been designed. The setup helps in the measurement of ac losses accurately, even for long samples.

Research conducted on the production of Hg0.8Pb0.2Ba2ca2cu3O8+ thick film superconductors onto Ag using Pb0.2Ba2ca2cu3O7+ precusor by the dip-coat method, shows that phase purity and the size of aligned grain colonies were increased when the films were buried in precursor powder.

Ba additions in Bi-2212 superconductors are investigated to determine microstructural development and superconducting properties.

The objective of nuclear magnetic resonance at 1 GHz, depending on superconductor and associated coil technology availability for the field, is examined.

La3+ substitution for Sr2+ and its influence on phase formation, structure and properties of (TI0.5Pb0.5)Sr2Ca2Cu3Oy compounds, was investigated.

A study was conducted on the influence of mechanical strain and properties in Bi2Sr2CaCu2Ox/AgMg composite conductors. Large mechanical strains may result in irreversible damage and low strains may cause crack propagation which restricts the conductors' applications. Two devices were developed for analyzing the influence of strain on high temperature superconducting tapes. Results show that effects of cyclic fatigue on critical current density.

A study was conducted on the fabrication and characterization of high temperature superconducting joints in BSCCO 2212/Ag composites performed by the National High Magnetic Field Laboratory. The laboratory employed a wrap joint technique in producing several prototype generations based on different combinations of fill materials, monocore and multifilament tapes and other stock conductors. The joints developed exhibit critical currents higher than those of unjoined conductor sections.

Nanosize MgO- and TiO2-doped 2212 powder were used to fabricated Ag-sheathed tapes. Unlike the TiO2 additions, no degradation in the superconducting properties were observed with the MgO additions. The MgO-doped samples also exhibited critical current density of up to 50,000 A/cm2 under heat treatment studies. The MgO, which was found compatible with the 2212 superconductor, maintained excellent size despite heat treatment.

The program at the National High Magnetic Field Laboratory for the design and development of 1 GHz class NMR magnets is described. The parameters are given for a 1.066 GHz magnet incorporating an HTS inner coil. The design of the related wide bore 900 MHz conventional superconductor magnet is described. Aspects of the technology development program supporting these designs are presented.

Direct current magnetic measurements are performed to study the flux pinning properties and anisotropic behavior of neutron irradiated HgBaCaCuO superconductors. Magnetic relaxation and magnetic hysteresis are measured with respect to the superconductors' critical current density and temperature. Results indicate the presence of a surface barrier that exhibit strong pinning effects.

The thermal stability of maglev superconducting magnets (SCMs) is not affected significantly by SCM-ground coil interactions. Earlier research has revealed that electrodynamic maglev separation is significantly affected by the quenching of superconducting magnets. The quenching is simulated by the interaction of the magnet with the highway. The quenching process limits the velocity of the maglev.

A study of 10 MWh superconducting magnetic energy storage systems (SMES) is conducted in relation to future trends in magnetic coil design. Recent innovations in materials technology and magnet engineering are also discussed to assess their effect on the design and economics of such systems. Results show that the advanced materials lead to higher current density, operating temperature and permissible stress which in turn can lower the cost of SMESs.