【摘要】 本文介绍了一种用于合成平均尺寸小于 1μm的超细YBa2 Cu3O7-δ(Y 12 3)粉末的固态反应法 .合成Y 12 3粉末的传统方法是利用BaCO3、Y2 O3和CuO粉末直接固态烧结反应 .本文介绍的方法则利用BaCuO2 ( 0 11)、Y2 O3和CuO粉末之间的固态反应 .本方法不包括传统反应法中限制反应速率的BaCO3分解反应 ,因而与传统固态反应法相比 ,其合成温度及保温时间大大降低 ,从而可以合成超细粉末 .将 0 11、Y2 O3 和CuO粉末按 4∶1∶2的摩尔比混合后在90 0℃于流通氧气中烧结 15小时 ,此时反应刚好完成而生成的Y 12 3粉末又不过分长大 ,得到的粉末平均尺寸小于 1μm .更多还原

【Abstract】 A solid state reaction process for the synthesis of ultrafine YBa-2Cu-3O-{7-δ} (Y-123) powder with an average size below 1 micron has been developed in this study. The conventional solid state reaction process to prepare Y-123 powder adopts the direct reaction of BaCO-3、Y-2O-3 and CuO powders. In the present study, however, a reaction among BaCuO-2 (011)、Y-2O-3、CuO powders is employed. In this method, the decomposition of BaCO-3, which is the major reaction rate limiting step in the conventional solid state reaction process, is excluded and so the sintering temperature and holding time required for the completion of the reaction decrease. By sintering the mixture of 011、Y-2O-3、CuO powders in a molar ratio of 4∶1∶2 at 900℃ for 15 hours in flowing oxygen, when the reaction has just been completed and Y-123 particles have not over-grown up, pure Y-123 powder less than 1 micron in diameter can be produced.更多还原