| 摘要 |
PURPOSE:To obtain a superconducting material with stabilized high critical temperature, by substituting part of the La by another lanthanoid element in a Ba-La-Cu-O superconducting material to make the crystal grains finer and increase the crystal grain boundaries. CONSTITUTION:First, each powder of Ba-contg. compound, La-contg. compound, Cu-contg. compound and element beta (selected from Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu)-contg. compound is prepared. Thence, these powder are blended in such proportion as to obtain a composite oxide of composition of formula [the rate of the element beta to La is 1-90atom.% and (La,beta) means that these elements occupy specific crystal sites in specific rates, y being such as to be 0<y<1] after the calcination. The resulting blend is then calcined, ground and formed followed by sintering the resultant form, thus obtaining the objective superconducting material of the composition of the formula. |
