| 摘要 |
PURPOSE:To obtain a superconducting composition having a stable, high critical temperature by blending powder of each simple substance or compounds of element of IIa group of the periodic table except Tl and Ba in a given ratio, calcining, grinding to give raw material powder and sintering the powder. CONSTITUTION:Powder of each simple substance of element beta(e.g. Ca) of group IIa of the periodic table except Tl and Ba, Ba and Cu or powder of compounds, oxides or precursors (e.g. carbonate) thereof is collected in a given ratio and blended. Then the blend powder is calcined at >=750 deg.C for 1-50hr to give a calcined material, which is ground by a ball mill, etc., to give calcined powder having <=10mu particle size. The calcined powder is used as raw material powder, optionally molded, sintered at >=750 deg.C for 1-50hr and optionally these operations are repeated to give a superconductor, a compound oxide having a composition shown by the formula TlxbetayBaCuzOa (0.5<=x, y<=3.0; 0.9<=z<=4.0). |
