| 摘要 |
PURPOSE:To readily obtain a Bi-based superconductor of 2,212 phase having a high critical temperature by blending raw materials containing Bi, Sr, Ca, Mg, Li and copper in a specific ratio, calcining, grinding, molding and burning in a nitrogen atmosphere. CONSTITUTION:Raw materials containing bismuth, strontium, calcium, magnesium, lithium and copper are weighed and blended to give a composition shown by the formula (A is 0.6-1.2; B is 0.35-0.7; C is 0.05-0.2; D is 0.05-0.2; figure shows atomic ratio). Then the mixture is calcined, ground, molded and burnt in a nitrogen atmosphere or a nitrogen atmosphere containing <10vol.% oxygen to give an oxide superconductor shown by the formula. Consequently, a Bi-based oxide superconductor of 2,212 phase showing >=90K critical temperature can be produced without requiring a quenching process. Therefore a large-sized molded article can readily be prepared. |
