抄録
As well-known that partial substitution of a Pb for Bi in the Bi-Sr-Ca-Cu-O system has been found to sharply increase the volume fraction of the high-Tc phase when both the starting material and the heating process are appropriate. This paper discusses the influence, in this case of the CaCO3 or CaO used as a raw material of Ca and the cold isostatic pressing (CIP) method on the superconducting properties of Bi1.8Pb0.4Sr2Ca2+xCu3.2Oy prepared by the solid-atate reaction. The superconducting characteristic obtained from the electrical resistance for the specimens sintered at 850°C for 200h, became gradually lower from 105K to 70K with increasing a Ca content from O to 0.8 mol. The Jc value increase with x was a maximum of 1820A/cm2 at x=0.4 sintered at 850°C to 200h.
