R. Cloots et al., STUDY OF THE CRYSTALLIZATION PROCESS IN BI2-XPBXSR2CA2CU3O10-Y GLASS SYSTEMS - OPTICAL POLARIZED-LIGHT MICROSCOPY, ELECTRICAL AND MAGNETIC-PROPERTIES, Superconductor science and technology, 6(12), 1993, pp. 850-857
Synthesis of Bi2-xPbxSr2Ca2Cu3O10-y (x = 0 and x = 0.3) has been perfo
rmed using the glass recrystallization route technique. After splat qu
enching, the samples were annealed at 820, 850 or 870-degrees-C for 96
or 144 h (with one intermediary grinding). High-resolution polarizati
on micrographs and electrical (and magnetic susceptibility) measuremen
ts have been taken. Various growth mechanisms can thus be checked, and
the physical properties are studied in relation to the microstructure
. It is found that the 2223 phase does not crystallize directly from t
he amorphous one but results from a dissolution-reprecipitation proces
s. The stability of the 2212 phase is emphasized. The 2201 phase preci
pitates at high temperature and rapidly reacts with the melt to form t
he 2223 phase. The kinetics of the lead-substituted sample seems to be
controlled by the Ca2PbO4 phase. which acts as a flux.