Influence of annealing in oxygen and argon on the superconducting properties of Li-doped YBCO single-grain bulks

Relationship between local microstructure and superconducting properties of commercial YBa2Cu3O7−δ bulk

“…However, chemical elemental mapping of the bulk using SEM in the vicinity of the seed did not detect neodymium that most probably could be caused by its concentration below energy dispersive x-ray spectroscopy detection limit which is 0.1 wt%. The inhomogeneities in the sample 1c interact with the flux lines as effective pinning centres similarly to Y123doped superconductors [33][34][35] and display appearance of clear peak effect at temperatures below 77 K (figure 9(a)). The pronounced peak effect in the sample 1c indicated that the size of created pinning centres or the mean distance between them should be close to two coherence lengths, ∼ξ ab , [36,37] that could be obtained, for example, in the samples with low chemical doping [33,35].…”

Characterization of High-Temperature Superconductor Bulks for Electrical Machine Application

“…For the two YBaCuO bulks presented in Figure 11, the measured B PM was around 1 T (red arrow). B P was deduced from B PM using Equation (7) and knowing e and L. J C was deduced from B P with Equation ( 6) and with n taken as equal to 50, giving a result of 110 A/mm 2 . This method has two main limitations.…”

“…This means the determination of the critical current density J C . Different classical methods have been used for small samples [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. The goal of these classical methods is mainly to obtain the dependence of J C on the magnetic field B and temperature of the HTS material.…”

Influence of CeO2 on microstructure, cracking and trapped field of TSIG YBCO single-grain superconductors

“…Defects which are introduced into the melt-grown YBCO bulk superconductors during the solidification process influence the overall superconducting and mechanical properties of the fabricated monoliths. In the case of YBCO bulk single-grain samples prepared by TSMG process, a number of reports describe the microstructural behaviour during the fabrication such as chemical phases present in the material, the size and the orientation of the crystal, growth front and growth mechanisms, subgrain formation [8][9][10][11][12][13][14][15][16][17], the size and volume fraction of Y211 particles [18][19][20][21][22][23][24][25][26][27], or crystal defects which arise after oxygenation such as cracks, twins, stacking faults [28][29][30][31][32][33][34][35], oxygen-deficient regions etc, and their impact on superconducting properties. The most important thing is to achieve high criticall current density by introducing effective pinning centres into the single-grain phase of YBa 2 Cu 3 O 7 (Y123).…”