PURPOSE: To obtain the subject oxide superconductor having a high critical current density even in a high magnetic field by dispersing Ca2PbO4 in a crystal grain of a Bi-Pb-Sr-Ca-Cu-O-based oxide superconductor having a specified composition.
CONSTITUTION: The subject oxide superconductor has a composition, Bia-Pbb-Src- Cad-Cue-Ox and contains Ca2PbO4 dispersed in its crystal grain, provided that 1.5≤a≤2.5; 0≤b≤0.5; 1.5≤c≤2.5; 0.5≤d≤2.5; 1.5≤e≤3.5; 7≤x≤17. For production of the above-mentioned oxide superconductor, the raw materials such as Bi2O3, PbO, SrCO3, CaCO3 and CuO are blended in a prescribed ratio and a superconductor is produced using the conventional method followed by heat treatment thereof in an atmosphere of 10% Ar and 90% O2. In addition, the size of Ca2PbO4 is preferably 0.01-10μm and the volume ratio occupied by the oxide in the whole superconductor is preferably 0.1-10vol.%.
KAMO YUICHI
MATSUDA SHINPEI
