Abshact-YB~Cu30x (YBCO) films have been deposited on buffered metal substrates by metal organic chemical-vapor deposition (MOCVD). Nickel alloy substrates with biaxirdlytextured yttria-stabilized zirconia (YSZ) buffer layers deposited by ion-beam-assisted deposition (IBAD) were used. A liquidstatic precursor delivery system was designed, constructed, and used in the MOCVD facility at Intermagnetics for the reported work. At 77 & under self-field conditions, we achieved a critical current (Q of 97.5 A in YBCO film grown by MOCVD on an IBAD substrate. This ICcorresponds to a critical current density of 1.3 MA/cm2 and 130 A/cm width of tape.

No abstract

Short and long periods of sintering of short single-core (Bi, Pb) 2 Sr 2 Ca 2 Cu 3 O 10+x tapes have been studied. Comparisons are made between three batches of these tapes with the same thermomechanical deformation and sintering conditions but with the starting precursor powders having undergone different processing. It is found that the volume density of the macroscopic pinning force in fields up to 1 T is greater for a particular sintering period. Resistivity measurements further show that the pinning activation energy also reaches a higher value for the same chosen sintering period. SEM images of the surfaces indicate that better core morphology and density can be achieved with this particular sintering period. Prolonged sintering leads to greater porosity while short-duration sintering inhibits grain growth and thus is of no assistance in the healing of cracks induced during the intermediate deformation between sintering periods.

No abstract