| 摘要 |
PURPOSE:To obtain the subject raw material having a low carbon content and capable of providing the subject superconductor having a high critical temperature by blending raw materials respectively containing Ba, Ca and copper in a specified ratio, carrying out preliminary calcining, grinding, calcining and regrinding and adding a specified amount of a Tl-containing raw material thereto. CONSTITUTION:Respective raw materials containing thallium, barium, calcium and copper are weighed out so that the atomic ratio of thallium : barium : calcium : copper may be (1.8-4.1):(1.8-2.1):(1.9-4.1):(2.9-5.1). The raw materials containing barium, calcium and copper are initially subjected primary blending and subsequently subjected to preliminarily calcination, grinding, calcination and regrinding. To the obtained ground material the thallium-containing raw material is then added and the secondary blending is carried out to obtain the subject raw material for a superconductor containing thallium, barium, calcium and copper in the above mentioned atomic ratio and containing <=0.7wt.% carbon in the whole composition. In addition, the objective saperconductor having a high critical temperature is obtained by sintering the above obtained raw material. |
