Transport and magnetisation measurements of Tl-1223 tapes - The nature of current paths and the role of grain boundaries at high magnetic fields

Conference item

The key factors that make the thallium-based 1223 phase conductors attractive candidates for high field applications are a high transition temperature (similar to 115 K), and an irreversibility line comparable to YBa2Cu3O7, However, a third important factor is the grain boundary behaviour. We have made detailed transport current-voltage (I-V) and magnetic studies of a Ag-0.1%Hf sheathed Tl-1223 tape. For low fields (B < 100 mT) its critical current density J(c) performance displays the ''weak-link'' signatures well-known for polycrystalline YBa2Cu3O7. At high fields however (B > 100 mT) there is a plateau region in its J(c)(B) characteristics. Possible scenarios for inter-granular transport current conduction and dissipation in this region are discussed.

Authors: Everett, J; Johnston, MD; Perkins, G; Volkozub, A; Caplin, A

• Publication status: Published
• Journal: IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
• Volume: 7
• Issue: 2
• Pages: 1965-1968
• Publication date: 1997-06-01
• Event title: 1996 Applied Superconductivity Conference
• DOI: 10.1109/77.620972
• ISSN: 1051-8223
• Keywords: T-C SUPERCONDUCTORS; TEXTURE; CONDUCTION; MODEL; microstructure; CRITICAL-CURRENT DENSITY; SILVER-SHEATHED TAPES; MECHANISMS; HIGH-TEMPERATURE SUPERCONDUCTORS; THIN-FILMS