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For some applications, short unit lengths of HTS wires should be spliced if longer lengths are necessary and short unit lengths of HTS wires should be utilize by applying the splice technology to reduce the total wire cost in the application. The splice technology has been developed for DI-BSCCO Type HT-CA tapes by Sumitomo Electric and spliced tapes were tested in Russian Cable Institute. The test program included: measurements of splice's resistance, critical current anisotropy, thermo cycling tolerance, mechanical properties, overload tests and magnetization measurements. In the paper the results of tests are presented and discussed. The test results demonstrated that splices can be used for cable production if twisting and bending limitations are taken into account.

We have studied the quasi-binary phase diagrams of RE–Ba–Cu–O systems, in which rare earth (RE) site is composed of Nd, Sm and its mixture, along the line connecting RE123 and Ba 3 Cu 5 O y (035) in 1% O 2 and 21% O 2 in Ar. The nucleation and melting of REBa 2 Cu 3 O y and RE 2 BaCuO 5 /RE 4 Ba 2 Cu 2 O 10 were observed in situ and the liquidus lines were determined using a laser-scanning microscope. Phase identification was performed on the samples quenched from high temperatures through X-ray powder diffraction measurements and electron probe microanalysis.

We have studied the quasi-binary phase diagrams along the line connecting NdBa2Cu3Oy and BaCuO2+w in reduced oxygen atmospheres: p(O2) = 10-3 and 10-2 atm. The nucleation and melt of NdBa2Cu3Oy (Nd123) in Ba-rich solvent were observed in situ using a laser scanning microscope in 1% O2 + Ar and 0.1% O2 + Ar. The liquidus and solidus lines of nearly stoichiometric Nd123 have been constructed. We have found that phase relations are quite different between 1% O2 + Ar and 0.1% O2 + Ar. In a 0.1% O2 + Ar environment BaCuO2+w undergoes incongruent melting (BaCuO2+w→Ba2CuO3+z + L→BaO + L) and Nd422 decomposes into the Nd2O3 phase.

It is known that the amount of Nd ions substituting for a Ba site in the Nd1+xBa2−xCu3Oy solid solution (Nd123ss) tends to decrease with either decreasing oxygen partial pressure PO2 or increasing temperature, however, the precise solubility limit of Nd123ss has not been obtained. In the present study, we carefully studied the solubility limit of Nd123ss under low PO2 and for the first time could show the presence of x

Unlike Y-Ba-Cu-O, the Nd-Ba-Cu-O system forms a Nd1+xBa2-xCu3O7-δ-type solid solution (Nd123ss). An understanding of PO2 and temperature dependence of the solubility limit will be the key to obtaining high Tc and Jc Nd123ss materials. Therefore, we carefully studied the solubility limit of Nd123ss as a function of PO2 and temperature. Through X-ray diffraction and differential thermal analysis measurements, we have found that Ba can substitute for Nd site under low PO2 at high temperatures. Furthermore, DC magnetization measurements showed that the superconducting transition temperature of Ba-rich Nd123ss (x

We have studied the quasi-binary phase diagram along the line of NdBa2Cu3Oy and BaCuO2 in 1%O2+Ar. In this study, the nucleation and melt of NdBa2Cu3Oy in Ba-rich solvent were observed in situ using a laser-scanning microscope under 1%O2+Ar. The liquidus and solidus lines of nearly stoichiometric Nd123 were constructed. Phase identification has been performed on the samples quenched from the reaction temperatures determined by differential thermal analyses through X-ray powder diffraction measurements and scanning electron microscopy.

Nd-Ba-Cu-O superconductors forms aNd1+xBa2-xCu3Oy solid solution (Ndl23ss). In general the solubility limit is dependent both on the oxygen partial pressure (PO2) and temperature, and therefore an understanding of PO2 and temperature dependence of the solubility limit will be an important guideline for obtaining high T c and J c materials. We carefully studied the solubility limit of Nd l23ss under low PO2 and at high temperatures. X-ray diffraction, thermal analysis and DC magnetization measurements confirmed that Ba can substitute for Nd site and the solubility limit for the Ba rich direction lies on x < 0 in low P O2 at high temperatures. Furthermore, Demagnetization measurements showed thatNdl23ss withx