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The magnetic properties of SmBa2Cu3O7-x (SmBCO) coated conductor (CC) that was fabricated on LaMnO3(LMO)/IBAD-MgO substrates using Evaporation using Drum in Dual Chamber (EDDC), which is a batch type co-evaporation system, was investigated. LMO buffer layer was deposited on IBAD-MgO templates by PLD method. The measurements of both the magnetization M(H) and the resistance R(T) for the SmBCO CC, were carried out at temperatures between 10 and 120 K in fields up to 8.5 T, using a PPMS-9T (with both ACMS and DCR options, Quantum Design). The SmBCO CC exhibited Tc (onset temperature) of 94.7 K with a narrow transition width of 0.6 K, which indicates a good homogeneity of the superconducting properties. The upper critical field Hc2 near Tc of the SmBCO CC has been estimated by the resistance R(T) approaches. The magnetization curves M(H) are symmetric about the line M = 0 for the SmBCO CC with the field applied parallel to both the c-axis and c-axis +45°. For the SmBCO CC with the field applied parallel to the ab-plane, they are asymmetric. These symmetric and asymmetric curves can be explained by introducing the bulk pinning of 1-D flux lines and surface barrier-dominated system of 2-D pancake vortices.

SmBa2Cu3O7 (SmBCO)-coated conductors were grown on IBAD-MgO templates by in-situ co-evaporation using a drum-in-dual-chambers system. The conductors, which had a coating thickness of up to 3 μm, showed a critical temperature of 92 ~ 94 K and a critical current of 150 ~ 625 A/cm-w at 77 K in a self-field. The phonon modes and cation disorder of the SmBCO-coated conductors were examined by polarized Raman scattering spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy. XRD showed (00l) peaks for the SmBCO phase. The Raman spectra revealed common vibration modes, including Ba-Ba stretching, Cu2-Cu2 stretching, O(2)+/O(3)-, and apical O(4) modes. In addition, polarized-Raman spectra were obtained to examine the crystal orientation and grain growth behavior. Structural information from the Raman spectra turned out to be useful to determine the optimal thickness of SmBCO-coated conductors with high critical currents.

In superconducting cable applications using the HTS tapes, striation of ReBCO coated conductor (CC) is being considered to reduce ac loss. The striation of ReBCO coating film with laser patterned filaments has been tried. In practical applications, the striated ReBCO CC tapes should also exhibit acceptable tolerance to mechanical stress/strains. However, reports on the electromechanical properties of striated CC tapes in bending or torsion mode are limited. In this study, the critical current degradation behavior of the striated Cu stabilized SmBCO CC tapes in pure torsion mode was investigated using a sample holder which gives torsional deformation to CC tapes. The CC tape has been laser scribed to produce multi-filaments. The Ic/Ic0 and n-value-torsional angle (θ) behaviors in the striated SmBCO CC tapes were examined and compared with the case of non-striated ones. According to the location of the coating film strip striated within the cross-section, there existed some difference in the Icf degradation behavior indicating that a non-uniform deformation was induced on each striated strip.

Effect of filament configuration and heat treatment of Bi2212/Ag round wire with low Ag ratio on the engineering critical current density (Je) was reported. We have fabricated 557, 85 7, and 121 7 wires with different Ag ratio and evaluated at various wire diameters. We have also changed the parameters of heat treatment. The effects of maximum process temperature (Tmax)and soaking time at Tmax and average filament diameter on the Je were also studied. 121 7 wire of 0.95 mm diameter heat-treated at showed Je of 858mm2 at 4.2K, 0 T.

SrRuO3 thin films have been grown in-situ on and LaAIO3 textured metal templates by pulsed laser deposition. Deposition was carried out between 3 mTorr to 300 mTorr of oxygen partial pressure with laser repetition rate of 5 Hz. Substrate temperature was between 500 and 800degC . Dependence of out-of plane orientation SrRuO3 of thin films on pressure and growth temperature is investigated by X-ray diffraction. The surface morphology and grain growth behaviors of thin films are analysed by atomic force microscopy. In addition, a ferromagnetic transition at ~150 K SrRuO3 of films on LaAIO3 is detected by resistivity and magnetization measurement.

The degree of ferromagnetism of Ni-Wy alloys decreases as W-content y increases. Both the saturation magnetization M sat and Curie temperature T c decrease linearly with W-content y, and both M sat and T c go to zero at critical concentration of yc ~9.50 at.% W. To compare with Ni-W alloys, the magnetic properties of a series of both as-rolled (non-textured) and annealed (biaxially textured) [Ni97at.%-W3at.%]100-x-Cux alloy tapes with compositions x = 0, 1, 3, 5, and 7 at.%, were studied. Characterization methods included XRD analyses to investigate the biaxial texturing of the annealed [Ni-W]-Cu alloy tapes and studies of the magnetization for both as-rolled and annealed [Ni-W]-Cu alloy tapes. Both the isothermal mass magnetizations M(H) of a series of samples at different fixed temperatures and M(T) in fixed field, were measured. The effect of Cu addition on both the saturation magnetization and Curie temperature Tc of the Ni97at.%-W3at.% alloy was investigated.

To investigate the effect of Ag or SiC nano-powder additions on the superconducting properties of MgB/sub 2/, a series of superconducting (Ag)/sub (x)wt.-%/(MgB/sub 2/)/sub (100-x)wt.-%/(Ag/sub x/-MgB/sub 2/) and (SiC)/sub (x)wt.-%/(MgB/sub 2/)/sub (100-x)wt.-%/((SiC)/sub x/-MgB/sub 2/)(0/spl les/x/spl les/20), containing Ag and SiC nano-powders, respectively, of different diameters (30 nm and 130 nm), were prepared by a simple solid-state reaction route, cold-pressed into a pellet form and investigated. To maintain the same environment of MgB/sub 2//stainless-steel tapes/wires, Ag/sub x/-MgB/sub 2/ and (SiC)/sub x/-MgB/sub 2/ pellets made out of the mixed powders were put inside stainless steel tubes and then sintered at 900/spl deg/C for two hours in Ar atmosphere. Characterization performed included both X-ray diffraction and magnetization. No impurity phase was identified for as-rolled samples. However, both the Ag/sub x/-MgB/sub 2/ and (SiC)/sub x/-MgB/sub 2/ composite pellets, when sintered, contain various impurity phases. The isothermal magnetizations M(H) of a series of samples were measured at temperatures between 5 and 50 K in fields up to 5 T, using a PPMS-9 (Quantum Design). The optimal amounts of Ag and SiC nano-powder in Ag/sub x/-MgB/sub 2/ and (SiC)/sub x/-MgB/sub 2/ to obtain the largest flux pinning effect are /spl sim/8 and /spl sim/4 wt.-%, respectively. The "two-step" structures in ZFC M(T) curves of (SiC)/sub x/-MgB/sub 2/ were more developed than Ag/sub x/-MgB/sub 2/. The best flux pinning centers can be created by adding a suitable size and amount of SiC nano-powder, not too large to increase the decoupling between the MgB/sub 2/ grains.