Presentation Information
[WB6-03]Recent Developments in Ternary LREBa2Cu3Oy Superconductors Prepared by Top Seeded Infiltration Growth
*Muralidhar Miryala1, Akash Garg Agarwal1 (1. Shibaura Institute of Technology (Japan))
Keywords:
Ternary LRE123,Infiltration growth,Air Process,Critical current density,Microstructure analysis
Superconducting super-magnets are finding increasing applications, driven by high-temperature superconductors (HTS) with critical temperatures (Tc) above liquid nitrogen’s boiling point (77.3 K). Among them, (RE)Ba2Cu3O7-x (RE=rare earth elements) "RE-123” is one of the most extensively studied, powering technologies such as NMR/MRI, magnetic levitation, flywheel energy storage, water purification, and magnetic separation systems [1]. Within this family, mixed ternary (LRE)Ba2Cu3O7-x “LRE-123” compounds exhibit enhanced superconducting performance due to compositional inhomogeneity introduced by multiple RE elements, particularly when processed by oxygen-controlled melt growth (OCMG). A notable example is the (Nd,Eu,Gd)Ba2Cu3O7-x bulk superconductor, which achieved record Jc values at self-field, an irreversible field of 15 T at 77 K, and a secondary Jc peak nearly 70 kA/cm2 higher than other RE-123 systems [2]. These properties originated from nano-lamella pinning centers formed through optimized RE ratios, effectively strengthening flux pinning and irreversibility fields. Further studies on systems such as (Nd,Eu,Gd)Ba2Cu3O7-x and (Sm,Eu,Gd)Ba2Cu3O7-x revealed that low-melting-point RE elements promote nanoscale (RE1,RE2,RE3)2Ba1Cu1O5 “RE-211” secondary phase particles, enabling record Jc values at 90.2 K and, for the first time, levitation demonstrations at this temperature [3]. However, the reliance on OCMG limits large-scale production, while infiltration-growth (IG)-processed mixed systems remain underdeveloped [4,5].
This presentation addresses these challenges by focusing on air-based fabrication of ternary LRE-Ba2Cu3O7-x (LRE = Sm, Eu, Gd) superconductors using the top-seeded infiltration growth (TSIG) process. By tailoring liquid compositions, the study demonstrated that the optimal choice reduced the size of the RE-211 secondary phase by 35%, resulting in a 136% increase in self-field critical current density and a 42.92% improvement in trapped field performance. The research identified RE-Ba2Cu3Oy + Ba3Cu5O8 as the most effective liquid source composition for fabricating ternary LRE-Ba2Cu3Oy superconductors in air. Furthermore, the influence of different rare-earth elements on superconducting properties was investigated. When YBa2Cu3Oy + Ba3Cu5O8 was used as the liquid source, the RE-211 particle size decreased by 38.41%, while the self-field Jc improved by 93.8%. This composition also produced a sharper superconducting transition (DeltaT < 4 K), representing a 53% improvement over other liquid sources. In addition, the effects of BaO2 (4 wt.%) and Ag2O additions were studied. These modifications yielded a record onset Tc of 94.5 K with a narrow transition width of just 0.88 K. The addition of Ag2O also enhanced high-field Jc and the irreversibility field, further advancing the performance of these materials. Together, these findings demonstrate practical pathways for reliable air-based fabrication of ternary LRE-Ba2Cu3Oy bulk superconductors, paving the way toward industrial-scale production and broad technological applications. References
1) J.H. Durrell, et al., Supercond. Sci. Tech., Vol 31, pp103501, 2018.
2) M. Muralidhar, et al., Phys. Rev. Lett., Vol 89, pp237001, 2002.
3) M. Muralidhar, et al., Appl. Phys. Lett., Vol 85, pp3504, 2004.
4) M. Muralidhar, & P. Sunsanee, J. Alloys Compd., Vol 997, pp174745, 2024.
5) A.G. Agarwal, & M. Miryala, Ceram. Int., Vol 50, pp31559, 2024.
This presentation addresses these challenges by focusing on air-based fabrication of ternary LRE-Ba2Cu3O7-x (LRE = Sm, Eu, Gd) superconductors using the top-seeded infiltration growth (TSIG) process. By tailoring liquid compositions, the study demonstrated that the optimal choice reduced the size of the RE-211 secondary phase by 35%, resulting in a 136% increase in self-field critical current density and a 42.92% improvement in trapped field performance. The research identified RE-Ba2Cu3Oy + Ba3Cu5O8 as the most effective liquid source composition for fabricating ternary LRE-Ba2Cu3Oy superconductors in air. Furthermore, the influence of different rare-earth elements on superconducting properties was investigated. When YBa2Cu3Oy + Ba3Cu5O8 was used as the liquid source, the RE-211 particle size decreased by 38.41%, while the self-field Jc improved by 93.8%. This composition also produced a sharper superconducting transition (DeltaT < 4 K), representing a 53% improvement over other liquid sources. In addition, the effects of BaO2 (4 wt.%) and Ag2O additions were studied. These modifications yielded a record onset Tc of 94.5 K with a narrow transition width of just 0.88 K. The addition of Ag2O also enhanced high-field Jc and the irreversibility field, further advancing the performance of these materials. Together, these findings demonstrate practical pathways for reliable air-based fabrication of ternary LRE-Ba2Cu3Oy bulk superconductors, paving the way toward industrial-scale production and broad technological applications. References
1) J.H. Durrell, et al., Supercond. Sci. Tech., Vol 31, pp103501, 2018.
2) M. Muralidhar, et al., Phys. Rev. Lett., Vol 89, pp237001, 2002.
3) M. Muralidhar, et al., Appl. Phys. Lett., Vol 85, pp3504, 2004.
4) M. Muralidhar, & P. Sunsanee, J. Alloys Compd., Vol 997, pp174745, 2024.
5) A.G. Agarwal, & M. Miryala, Ceram. Int., Vol 50, pp31559, 2024.