Title :
Effects of Pb doping on the microstructure and superconductivity of bulk BSCCO 2212
Author :
Alamgir, A.K.M. ; Yamada, H. ; Harada, N. ; Osaki, K. ; Tada, N.
Author_Institution :
Fac. of Sci. & Eng., Yamaguchi Univ., Japan
fDate :
6/1/1999 12:00:00 AM
Abstract :
BSCCO 2212 suffers from intrinsic weak flux pinning above /spl sim/20 K. From the view point of practical applications, it is particularly important to expand the irreversible regime up to considerably higher temperatures. BSCCO 2212 (molar ratio Bi:Pb:Sr:Ca:Cu:O=2-x:x:2:1:2) bulk samples have been synthesized using partial-melt processing in air with Pb contents x up to 0.8. Pb doping has been shown to reduce the melting temperature as well as improve the irreversibility field, X-ray diffraction and scanning electron microscopy along with superconducting property measurement were carried out to investigate the phase evolution and microstructure. Melt texturing showed considerably large plate-like grains with enhanced 001 reflection peaks. Effects of the Pb doping on the melt processing and superconductivity as a function of temperature and magnetic field will be discussed.
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); crystal microstructure; flux pinning; high-temperature superconductors; lead compounds; strontium compounds; superconducting transition temperature; (BiPb)/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/; BSCCO 2212; Pb doping; enhanced 001 reflection peaks; high temperature superconductor; intrinsic weak flux pinning; irreversible regime; large plate-like grains; melt texturing; melting temperature; microstructure; partial-melt processing; phase evolution; superconductivity; Bismuth compounds; Doping; Flux pinning; Magnetic field measurement; Microstructure; Phase measurement; Scanning electron microscopy; Superconductivity; Temperature; X-ray diffraction;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
