| 摘要 |
<p>A superconducting substance of the invention is composed of a bismuth oxide, or a bismuth oxide in which Bi is partly substituted by Pb, Cr or V. It exhibits Tc of the class of 120 K. The superconducting substance is obtained by mixing raw material compounds of these components, and effecting the primary firing at lower than 820°C until no bismuth oxide is recognized and then effecting the secondary firing at 865 to 880°C. The composition represented by Bi2Sr2Ca2CuOx is characterized by the following properties: Tc - 120 K; a = 5.40 ± 0.20 Å, b = 27.0 ± 1.0 Å, c = 36.8 ± 1.0 Å, α = β = η = 90 ± 1° (lattice constant); 2υ = 4.86 ± 0.20°, 2υ = 24.04 ± 0.20°, 2υ = 26.25 ± 0.20° (peak positions of powder X-ray diffraction pattern using CuKα ray).</p> |
