Transport critical current densities in bulk Tl sub 2 Ba sub 2 Ca sub 2 Cu sub 2 O sub x and polycrystalline-thin-film Tl sub 2 Ba sub 2 Ca sub 1 Cu sub 2 O sub x; Dependence on microstructure and neutron irradiation damage

• Published in: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States) Vol. 27:2
• Main Authors: Maley, M.P., Vogt, G.J., Phillips, D.S., Coulter, J.Y., Arendt, P.N., Elliot, N.E.
• Format: Conference Proceeding
• Language: English
• Published: United States 01.03.1991
• Subjects: 360206 > Ceramics, Cermets, & Refractories > Radiation Effects; ALKALINE EARTH METAL COMPOUNDS; BARIUM COMPOUNDS; BARIUM OXIDES; BARYONS; CALCIUM COMPOUNDS; CALCIUM OXIDES; CHALCOGENIDES; COPPER COMPOUNDS; COPPER OXIDES; CREEP; CRITICAL CURRENT; CRYSTAL STRUCTURE; CRYSTALS; CURRENT DENSITY; CURRENTS; ELECTRIC CURRENTS; ELEMENTARY PARTICLES; FERMIONS; HADRONS; IRRADIATION; MAGNETIC FIELD CONFIGURATIONS; MAGNETIC FIELDS; MATERIALS SCIENCE; MECHANICAL PROPERTIES; MICROSTRUCTURE; NEUTRONS; NUCLEONS; OXIDES; OXYGEN COMPOUNDS; PHYSICAL RADIATION EFFECTS; POLYCRYSTALS; RADIATION EFFECTS; SUPERCONDUCTING FILMS; THALLIUM COMPOUNDS; THALLIUM OXIDES; TRANSITION ELEMENT COMPOUNDS 360207 > Ceramics, Cermets, & Refractories > Superconducting Properties > (1992-)
• ISSN: 0018-9464; 1941-0069

This paper reports investigations of the dependence of transport critical current density, J{sub c}, upon magnetic field, B at 4, 64 and 75 K in a bulk ceramic sample of T1{sub 2}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} and in a polycrystalline, textured thin film of T1{sub 2}Ba{sub 2}CaCu{sub 2}O{sub x}. In ceramic samples of T1-2223 we generally observe the double-step J{sub c} versus B characteristics first pointed out by Ekin, in which J{sub c} drops from its zero field value to a plateau reached at B{approximately}100 Oe. The plateau region then extends to a higher field B* (T) beyond which J{sub c}(B) decreases monotonically. We have achieved plateau J{sub c} (75 K. 1.OT) values {gt}300 A/cm{sup 2} with B* (75 K) {approximately} 1.5 T. In these samples a pronounced peak effect is observed in which J{sub c} (B) increases monotonically with increasing B for 100 {lt} B(O{sub e}) {lt} B*. After neutron irradiation, we observe B* to be significantly enhanced suggesting that B* signals the onset of rapid flux creep.