Using YBCO and NdBCO double-layer thin film crystal on MgO substrate and welded YBCO bulk superconductor manufactured by top seeded-melt-growth (TSMG) method

In this study, Y123 + %25Y211 (YBCO) samples and Y123 + %25Y211 + %20Ag2O (YBCO-Ag2O) welding sample were produced by using NdBCO/YBCO/MgO (300 nm NdBCO/ 20 nm YBCO/ MgO) thin film seed as seeding material and applying TSMG as production method to be used in technological applications. Two slices of approximately 1.5 mm thick were cut from the welding sample. Three YBCO samples and two addition materials were added parallel to the c-axis, stacked on top of each other. The superconducting ring was formed by applying the water jet method to the attached sample. In order to examine the superconductivity properties, resistivity and magnetization measurements of the small pieces cut from the welded bulks were made. As a result of the applied welded method, microcracks were encountered in the microstructure analysis of the samples and welding regions, while it was seen from the critical current density curves that the cracks did not prevent to the current flow, attached sample were resistant to the applied magnetic field as a whole and the resistance transitions were uniform (~ 92 K) as expected.