Effect of process parameters in the decomposition of a cryochemical salt product of the Bi-Pb-Sr-Ca-Cu-O system on the structure and properties of a ceramics

A study was made of the effect of the temperature and time of decomposition of a salt product on the phase composition, microstructure, and magnetic s usceptibility of a Bi - Pb - Sr - Ca - Cu - O superconducting ceramics. Hol ding the powder at 570 degreesC slows the formation of the high-temperature phases, while increasing the decomposition temperature to 840 degreesC and increasing the time of decomposition at 815 degreesC have the same effect on the concentrations of the phases Ca2PbO4, CuO, and (CaSr)(2)CuO3. The da ta obtained on magnetic susceptibility, together with the results of micros copic and x-ray spectral studies, made it possible to evaluate the effect o f the morphology of the grains and the grain boundaries on the superconduct ivity of the sintered specimens.