摘要
The evolution of microstructures during the phase conversion for the Bi(Pb)-Sr-Ca-Cu-O system has been studied for specimens with cumulative sintering. The changes of surface morphology, crystallinity, composition, weight and diameter were characterized for specimens sintered iteratively at a fixed temperature. Evaporation of Pb from the surface was found to result in a microstructural variation between surface and interior of specimens. The phase conversion for the sintered specimen was significantly enhanced by sintering the specimen with fresh powder pellet of the same composition. The enhancement is attributed to the change of Pb atmosphere during sintering treatment. © 1997 Elsevier Science B.V.