| 摘要 |
PURPOSE:To produce a bismuthal oxide superconductor being excellent in both its critical current density and its critical current in a manufacture of the bismuthal oxide superconductor comprising the steps of filling raw material powder in a metallic sheath, plastically processing them to produce wire rods followed by heat-treatment. CONSTITUTION:Prior to the step of plastic process to produce wire rods raw powder is heat-treated in such a way that the ratio of the 2212 phase, whose composition ratio of Bi or (Bi, Pb):Sr:Ca:Cu being approximately equal to 2:2:1:2, to the 2223 phase, whose corresponding composition ratio being approximately equal to 2:2:2:3, is adjusted to be in the range from 75 to 90: from 10 to 25. |
