| 摘要 |
PROBLEM TO BE SOLVED: To improve electromagnetic characteristics in air by adding a silver- contg. compd. to a source mixture of specified compds., melting the mixture in air at a temp. higher than the temp. to cause partial melting, keeping the mixture at a specified temp. or slowly cooling. SOLUTION: A source material mixture containing a RE compd. (RE is a rare earth metal element including Y), a Ba compd. and a Cu compd. is mixed with Al metal or an Al compd. by 1 to 60 wt.% (calculated as the weight of only Al element) and molten at a temp. higher than the temp. to cause partial melting in an atmosphere of 2×10 to 1 atm oxygen partial pressure P0 . Then the mixture is cooled to room temp. or if necessary kept at a specified temp. and slowly cooled to obtain an oxide superconductor having a phase of RE2(1-q) Ba1+r CuO5+s or a phase of RE4(1-q) Ba2(1+r) Cu2 O2(5+s) in a phase of RE1+x Ba2+y Cu3 Od phase. In the formulae, x, y, d satisfy -0.3<x<0.3, -0.3<y<0.3 and 6.5<d<7.5, and q, r, s satisfy -0.3<q<3.0, -0.3<r<3.0, and -0.5<s<5.0. |
