In this study, Y1.6Ba2.3Cu2.3Ox (YBCO) bulk superconductors were fabricated using a multiple-seeded melt-growth (MSMG) process. The number of seeds (n) varied from 1 to 6. Magnetic levitation forces at 77 K were measured for the YBCO samples cooled under field-cooled (FC) and zero-field-cooled (ZFC) procedures. The maximum repulsive force (Fmax) of the n = 1 sample under ZFC conditions was 64.7 N. As n increased to 4, 5, and 6, Fmax decreased to 60.9 N, 57.6 N, and 54.3 N, respectively. The reduction in Fmax with increasing n was less than 20% compared to the n=1 sample. In contrast, the Fmax of the YBCO samples measured under FC was lower than that measured under ZFC. Specifically, the Fmax of the n = 1, n = 4, n = 5, and n = 6 samples under FC were 19.9 N, 25.9 N, 23.9 N, and 23.9 N, respectively. Due to the magnetic flux pinning under FC, the attractive forces (22-24 N) were much larger than those (below 5 N) under ZFC. In both cooling conditions, the levitation forces slightly decreased as n increased. Despite the decrease in magnetic levitation forces with increasing n, the process offers the advantage of shorter processing times. Consequently, the MSMG process is considered a cost-effective method for producing large-area YBCO bulk superconductors.
목차
Abstract 1. INTRODUCTION 2. EXPERIMENTAL 2.1. Sample preparation 2.2 Levitation force measurement 3. RESULTS AND DISCUSSION 3.1. Top surface views of YBCO samples 3.2. Force-distance curve (ZFC) 3.3. Force-distance curve (FC) 4. CONCLUSIONS ACKNOWLEDGMENT REFERENCES
키워드
YBCO superconductorsmulti-seedingnumber of seedsmagnetic levitation forcescooling methods
저자
I. G. Park [ Department of Electronic Engineering, Sunmoon University, Asan-si, 31460, Republic of Korea ]
C.-J. Kim [ Superconductor Magnetic Levitation Technologies, Ltd., Republic of Korea ]
Corresponding Author
S. H. Lee [ Department of Electronic Engineering, Sunmoon University, Asan-si, 31460, Republic of Korea ]
Corresponding Author