Title :
On the evolution of phases in polycrystalline Li-doped 2212 BSCCO and enhanced superconducting behaviour via n(Li, alpha )T reactions
Author :
Schwartz, J. ; Wu, S. ; Raban, G.W., Jr. ; Rynes, J.C.
Author_Institution :
Illinois Univ., Urbana, IL, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
The authors report on the evolution of phases upon cooling of partially melted Bi-Sr-Ca-Cu-Li-O powders and tapes and on enhanced magnetic flux-pinning through irradiation. Enhanced resistive transitions have been obtained despite significant amounts of (Sr/sub 1- delta /, Ca/sub delta /)/sub n/CuO/sub x/ phases (n=1 or 2). The evolution of phases is investigated in Li-doped and undoped 2212 via extensive microstructural characterizations. To enhance the flux-pinning, Li-doped and undoped 2212 have been neutron irradiated. In addition to the neutron-collision-induced damage, fission reactions produce a homogeneous distribution of high- and low-energy charged particles. Effects of irradiation on the magnetically measured T/sub c/ and J/sub c.m/(H) are reported. Differences between the effects upon doped and undoped superconducting powders are discussed, highlighting the effects of the charged particle damage.<>
Keywords :
X-ray diffraction examination of materials; bismuth compounds; calcium compounds; critical current density (superconductivity); crystal microstructure; flux pinning; high-temperature superconductors; magnetisation; neutron effects; scanning electron microscope examination of materials; strontium compounds; superconducting transition temperature; surface structure; 2212 BSCCO; BiSrCaCuLiO tapes; SEM; X-ray diffraction; charged particle damage; critical current density; doped superconductor; fission reactions; magnetic flux-pinning; magnetisation; microstructural characterizations; n(Li, alpha )T reactions; neutron irradiation; neutron-collision-induced damage; partially melted powder; phases evolution; resistive transitions; surface analysis; transition temperature; undoped superconducting powders; Bismuth compounds; Cooling; Current density; Magnetic anisotropy; Neutrons; Perpendicular magnetic anisotropy; Powders; Superconducting films; Superconducting magnets; Temperature;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
