准静水冷压处理后的Bi_(0.8)Pb_(0.2)SrCaCu_2O_x超导材料  

QUASI-HYDROSTAT1CALLY COLD-PRESSED Bi_(0.8)Pb_(0.2)SrCaCu_2O_x, SUPERCONDUCTORS

作　　者：吴冰青[1] 王文魁[2] 靳常青[2] 刘维[2] 李方华[2] 刘世超[2] 刘振兴[2] 赵忠贤[3] 姚玉书[3] 

机构地区：[1]中国科学院表面物理国家重点实验室,北京100080 [2]中国科学院物理研究所,北京100080 [3]中国科学院超导国家重点实验室,北京100080

出　　处：《物理学报》1992年第12期1993-2002,共10页Acta Physica Sinica

基　　金：国家超导技术联合研究开发中心资助的课题

摘　　要：着重讨论了准静水冷压对Bi系高温超导材料超导电性的影响,并分析了经冷压-退火处理后超导电性的改善情况。准静水冷压处理后,Bi系超导材料晶粒间界连接发生显著退化,晶粒内部产生大量缺陷,由此导致了宏观超导电性的退化。冷压造成了体密度的极大提高和一定的晶粒择优取向。这些现象主要是由于准静水压下剪切应力的作用。退火后,晶界连接得到很大加强,部分缺陷消失或形成堆错使材料各项性能均获改善。Jc(77K,零场)较初始样品有大幅度提高,达约1600A/cm^2。此外还考察了静水压条件下Tc-p关系,有dTc/dp=1.4K/GPa。The effects of quasi-hydrostatic pressure treatments on the Bi-system superconductors were investigated The cold-pressing treatments seriously weakened the inter-granular weaklinks and induced a large number of intragranular defects, resulting in the deterioration of the suprcon-ducting properties. The targe increase in the bulk density and the orientation of the superconducting grains were also observed in the cold-pressed samples. These drastic changes of superconductivity were mainly due to the shear stress under quasi-hydrostatic pressure. The post annealing treatments greatly enhanced the weaklinks and caused the partial recovery and the agglomeration of some defects. By coldpressing-annealing method, J6 (77 K, zero field) was raised to about 1600A/cm2. The pressure dependence of T. under hydrostatic pressure was also investigated and dTc/dp was found to be 1.4K/GPa.

关 键 词：超导材料 铋 冷压 高温超导性 

分 类 号：O511.1[理学—低温物理]