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Critical current ([I.sub.c])-strain characteristic of YBCO coated conductor is measured by using a Walters spring (WASP). The results have shown that combined strain of bending and tensile strains are regarded as simple summation in the present YBCO coated conductor.

The evaluation of second-generation (2G) High Temperature Superconducting (HTS) wires for fault current limiter (FCL) applications is discussed. Results suggest that the 2G HTS conductor was successful in limiting the fault current to 32 kA at the first peak with 3.2 kA in the HTS elements.

Various advancements have been made in the development of [YBa.sub.2][Cu.sub.3][O.sub.x] (YBCO) second generation HTS conductor scale-up at superpower. These conductors are found to exhibit very high values of the critical current.

Reporting the investigation on the texture development and superconducting properties of YBCO films deposited on buffered metal substrates during our scale-up process is presented. The results demonstrate that high quality YBCO thick films with high critical current carrying ability is fabricated by PLD at very high deposition rate on buffered metal substrates.

The powder-in-tube technique was used to fabricate multifilamentary silver-clad Bi-2223 tapes with the precursor powder containing Pb-added 2212, Ca2PbO4, alkaline-earth cuprate and CuO phases and having the overall stoichiometry of Bi-2223. Varying the mechanical and thermal processes during tape processing improved the transport current properties in these multifilament silver-clad Bi-2223 superconducting tapes. Experimental methods and findings are presented.

Metal Organic Chemical Vapor Deposition (MOCVD) was used to deposit YBa2Cu3Ox (YBCO) films on buffered metal substrates. A thermonuclear process was used to fabricate cube-textured nickel substrates. Thermal evaporation was then used to deposit epitaxial CeO2 films on these substrates. MOCVD was also used to deposit highly biaxially-textured YBCO films on both types of metal substrates. The results showed that a critical current density greater than 10 to the fifth power A/cm2 at 77 K has been achieved in YBCO films on metal substrates.

The powder-in-tube (PIT) and surface-coated conductor methods were utilized in fabricating Tl-1223 conductors. Short monofilament tapes and meter-long 37-filament tapes exhibited current densities of 20,000 A/cm2 and 12,000 A/cm2 at 77 K, respectively. A new method was also proposed for the development of PIT Tl-1223 conductors with grain alignment. The approach successfully fabricated conductors with critical currents of 18 A and a 19,000A/cm2 Jc.

Alternating current (AC) transport current-induced energy losses were measured in silver sheathed mono core Tl-1223 and multifilamentary Bi-2223 tapes as a function of the applied external magnetic field's orientation and magnitude. The external magnetic field, which was rotated in the 0 to +/-90-degrees range, was kept perpendicular to the transport current flow. Transport current loss measurements in direct current (DC) applied fields were in agreement with Norris equation when the DC critical current is used for the expression of the loss.

Aligned-MgO whiskers are embedded in monofilamentary BSCCO 2223 tapes to improve their strain tolerance. The MgO whiskers, which were fabricated by means of the molten synthesis method, mixed with the tapes so that they account for 15% of the materials' volume. Resistivity, current density and temperature measurements show that the resulting BSCCO 2223 tapes have excellent resistance against bend strain.

The deposition of YBaCu3Ox films on buffered metal substrates using metal organic chemical-vapour deposition is described.

The crystallographic quality of the high textured structure of a YBa2Cu3Ox material was examined. Samples were fabricated by a liquid phase process. Electron spin resonance spectrometry coupled with continuous gas fow cryostat were used to obtain high sensitivity estimates of the temperature and direct current magnetic filed dependencies of the surface grain resistance of the sample bulk material. The nonlinear dependence of surface resistance to low magnetic fields was demonstrated.

Reporting the progress in scale up of YBCO, coated conductor at IGC-superpower using PLD and MOCVD and IBAD-based substrates is presented. These regions are analyzed using several characterization tools and undulations in the cap layer over the IBAD buffer, which related to the rough areas.