先位粉末套管法制备MgB_2/Fe线材的超导性能研究  

FABRICATION AND CHARACTERIZATION OF MgB_2/Fe BY EX-SITU PIT METHOD

作　　者：王栋樑[1] 张现平[1] 高召顺[1] 禹争光[1] 马衍伟[1] 闻海虎[2] 郭建栋[3] 

机构地区：[1]中国科学院电工研究所应用超导实验室,北京100080 [2]中国科学院物理研究所,北京100080 [3]北京大学物理学院,北京100871

出　　处：《低温物理学报》2007年第2期102-104,共3页Low Temperature Physical Letters

基　　金：国家自然科学基金(批准号:50472063;50377040);国家"973"项目(批准号:2006CB601004)资助的课题~~

摘　　要：采用先位法将MgB2粉装入纯铁管中,制备出MgB2/Fe超导线材.用X射线衍射仪和扫描电子显微镜分析了样品的物相组成和显微结构;用SQUID测量了样品的超导转变温度;用标准四引线法测量了短样的临界电流.结果显示,超导样品的临界转变温度约为38.3K,在4.2K/4T下MgB2/Fe线材的临界电流密度为～104A/cm2.研究结果表明,高温退火有效地减少了冷加工过程中产生的应力,改善了晶粒连接性,提高了芯材的致密度,可以显著地提高先位法制备线材的临界电流密度.The MgB2/Fe superconducting wires were fabricated by the ex-situ Powder-In-Tube （PIT） process. The samples were characterized using X-ray diffraction, scanning electron microscope, superconducting quantum interference device magnetometer etc. The Jc and its magnetic field dependence were evaluated by a standard four-probe technique. It is found that the critical transition temperature of the superconductor was about 38. 3K, and the Jc value was ～10^4 A/cm^2 （4. 2 K, g T）. The high temperature heat-treatment could effectively reduce the stress produced by cold deformation process, and improve the grain connection and the density of the superconducting wire, thus the Jc of the ex-situ wire was enhanced significantly.

关 键 词：MGB2 超导线材 先位法 粉末套管法 临界电流密度 

分 类 号：O511.4[理学—低温物理]