摘要
采用固相反应法合成了名义组分为Bi_(1.75)Pb_(0.3)Sr_2Ca_(2.3)Cu_(5.6)O_y的样品,对各种条件下烧制的样品进行了相结构分析,并测量了交流磁化率和电阻—温度关系。总结实验规律,以“高温”烧结后,“低温”分段处理的工艺路线,制备了零电阻温度为111K的单相多晶超导体。利用日本岛津DT—40热分析系统对该单相材料进行了热分析,结果表明,在800～900℃的高温下,样品周围的氧浓度越大,其超导相的结构越稳定,因而样品的熔点就越高。根据这一结论,我们进一步讨论了掺Pb有利于样品内高T_c相形成和稳定的原因。
A single phase high T,, of the ceramic supercondutor Bi-Pb-Sr-Ca-Ca-O was obtained by the solid state reaction method in air. The samples were annealed at different temperature, then quenched in liquid-nitrogen, We have found that the low Tc phase and other phases formed at the temperature lower than 840℃ and the high Tc phase is only formed at the temperature higher than 840℃. Based on these, We have prepared the high T,. single phase superconductor with zero-resistivity temperature T=111K from Bi1.75Pb0.2Sr2.0Ca2.3Cu3.8Oy by sintering at 'high temperature' and stage, treating at 'low temperature' .Also we have found the important faction of oxygen to the thermostability of this material.
出处
《低温与超导》
CAS
CSCD
北大核心
1992年第2期32-37,共6页
Cryogenics and Superconductivity
