| 摘要 |
PROBLEM TO BE SOLVED: To attain high critical current density by compacting and sintering calcined powder obtd. by blending components so as to give the objective compsn. and carrying out calcination and pulverization to a specified average particle diameter or below. SOLUTION: Powders of starting materials such as Bi2 O3 , PbO, SrCO3 , CaO and CuO are blended in a prescribed molar ratio and added to a mixed solvent composed of nonpolar and polar org. solvents such as benzene and methanol. They are mixed and dried to form a powdery mixture. This mixture is calcined at about 800 deg.C, wet-pulverized with a mixed solvent, and the solvent is eliminated by vacuum drying to obtain calcined powder having about <=0.1wt.% C content, about <=0.5wt.% H2 O content and <=2.0μm average particle diameter. This calcined powder is press-compacted and successively subjected to sintering at about 850 deg.C for 12hr, intermediate compression under about 3t/cm<2> , sintering, intermediate compressing and sintering to obtain the objective oxide superconductor such as a Bi-contg. oxide superconductor having about >=3,000A/cm<2> critical current density. |
