Effect of seed orientations on the crystallization characteristics and the magnetic levitation properties of single domain YBCO bulk superconductors

A Novel Top Seeding Method for Reliable Growth of Single-Grain YBCO Bulk Superconductor with High Levitation Property above 26 N/cm2

“…Using the values of F max (63.63 N) and the sample diameter (17.5 mm), the force density is calculated as 26.45 N/cm 2 , representing significantly high levitation property and meeting the demands of practical applications. In a recent study by Wu et al, one 20 mm as-pressed and c -axis-oriented YBCO sample fabricated by the 011-IG technique and using the conventional NdBCO crystal seed exhibits a F max value of 54.8 N. It can be seen that although the sample of this study is smaller (i.e., 16 mm as-pressed), it presents an even higher levitation property (63.63 N). The appearance of such a high property is attributed to the new processing that we recently developed for the 011-IG technique: (1) using commercial high-quality NdBCO/YBCO/MgO thin film as the seed to ensure high growth quality of the final YBCO single grains; (2) pressing precursor pellets using the novel divisible mold to eliminate macro and tiny cracks on the sample surface; (3) introducing a powder melting mechanism in the solid pellet through the addition of 5 mol % Ba 3 Cu 5 O 8 to control the bulk size expansion and reduce the inner porosity; (4) using Y 2 O 3 nanopowders and adding 1 wt % CeO 2 nanopowders in the solid pellet to further improve the microstructure.…”

Properties and Types of Superconductors

“…Few researchers have done work on inner growth rate (Rai) and growth rate of surfaces (Rcs) [98]. Efficient growth rate investigation neither depends on the a-axis, c-axis directions, surface or internal, the foremost important thing is crystal structure growth procedure of YBCO [99].…”

“…The reason is existence of NdBCO crystal seed's c-axis normal to the sample plane. This results in four fold a-axis growth sectors (a-GSs) by means of single domain YBCO bulk lying on apex surface of compounds [99].…”

“…Figure 9 [99] shows the Pa-Y123 group bulks with top surface morphology by means of caxis parallel to upper surface over changed super cooling temperature. The top surface of distinctive YBCO superconductor consisting of single domain is illustrated over variety of ΔT, with no arbitrary nucleation region is detected for all samples.…”

“…Pa-Y123 group is consisted of rectangular form, it is due to the upper surface of samples is along the c-axis of seed NdBCO. Such outcomes reveal that surface growth rate of Ras is lower than the Rcs of YBCO bulk when top surfaces of the samples are parallel to c-axis of seed NdBCO [99]. Cuprates are consisted of considerable materials after the innovation of high oxide superconductors [101], Bi-based high-temperature superconductors (HTSC).…”