粉末套管BPSCCO／Ag复合带载流各向异性特征的研究  

THE ANISOTROPIC CHARACTERISTICS OF A BPSCCO/Ag COMPOSITE TAPE PROCESSED BY POWDER-IN-TUBE

作　　者：张宏[1] 吴鸿[1] 曾飞[1] 

机构地区：[1]中国科学院上海冶金研究所

出　　处：《低温物理学报》1995年第3期223-232,共10页Low Temperature Physical Letters

基　　金：国家超导中心;中国科学院超导办资助

摘　　要：本工作采用直流传输电流和直流磁化行为的测量研究了经恰当热－机械处理后的ＢＰＳＣＣＯ／Ａｇ复合带的临界电流特性，表明：由于ＢＰＳＣＣＯ晶粒的强ｃ轴择优取向，传输和磁化临界电流密度呈现大的各向异性，磁场在ｃ轴的分量起有主要作用．因传输和磁化临界电流密度相应于各向异性临界电流密度的不同主分量，故它们随角度变化的行为不同．传输电流的Ｉ－Ｖ曲线和磁弛橡Ｍ－ｔ曲线都呈现幂指数关系，即分别为Ｖ∞ＡＩｎ和Ｍ∞Ｂｔ（－ｍ）．二者表明ＢＰＳＣＣＯ中磁通运动的钉扎势可以用对数势Ｕｅ＝Ｕ０ｌｎ（Ｊ（ｃ０）／Ｊ）描述．Abstract The characteristics of the critical current density of a BPSCCO/Ag composite tape processed by powder-in-tube was investigated using D. C.transport current and D. C.magnatization behaviour measurement. it, is shown that owing to the strong texture of BPSCCO grains with c axis parallel to the normal of the broad surface of the tape, the critical current shows strong anlsotropy and the component of magnetic field in the c axis direction plays an important role.Since transport and magnetic critical current density measured correspond different principal components of the critical current density in a crystal with layer structure,the behaviour of both critical current densities is different. Both the I-V relation in transport mesurement and magnetization relaxation in magnetic measurement can be well fitted by power law,i. e., V ∞AI' and M ∞ Bt-m respectively. That indicates that the flux pinning potential can be well described by Ue=U0ln(Jc0/J ).

关 键 词：超导体 复合带 临界电流特性 各向异性 粉末套管 

分 类 号：O511.1[理学—低温物理]