结合连续管线成型技术和粉末套管法制备SiC掺杂的MgB_2超导线材研究  

Study on Processing SiC-Doped MgB_2 Superconducting Wires by Combining Both CTFF Technique and PIT Method

作　　者：马麟[1] 索红莉[1] 张子立[1] 王朝[1] 高培阔[1] 刘敏[1] 赵跃[1] 曹玲柱[1] 李亚明[1] 周美玲[1] 

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100022

出　　处：《稀有金属材料与工程》2008年第A04期128-132,共5页Rare Metal Materials and Engineering

基　　金：北京市自然科学基金(2072004);国家教委全国百篇优秀博士论文专项资金(200331);国家自然科学基金(50771003);国家"973"计划(2006CB601005);北京工业大学111人才工程资助等项目的资助

摘　　要：结合连续管线成型技术和粉末套管方法,原位掺杂SiC制备出了20m长的单芯MgB2/Fe、MgB2/Nb/Fe线材和7芯、19芯及49芯的MgB2/Nb/Cu/Fe复合多芯线材。采用XRD和SEM分别对烧结后样品芯部进行相成分和微观结构研究,并通过TEM对SiC掺杂的机理进行了简单分析。采用四引线法对线材进行电流测量并获得临界电流密度。结果表明,线材经过不同温度保温15min的真空退火后,在800℃形成的MgB2相含量最高,其中单芯MgB2/Fe线材在4.2K,11T下Jc值超过104A/cm2,7芯复合线材在4.2K,7.5T下Jc值也达到104A/cm2,并且具有较好的热稳定性,在低场下仍可稳定通过电流。20 meters long in-situ SiC doped mono-MgB2/Fe, MgB2/Nb/Fe and 7-, 19-, 49-MgB2/Nb/Cu/Fe multi-filamentary wires have been fabricated by combining both continuous tube forming filling （CTFF） and powder in tube （PIT） processes. The phase compositions and microstructures of the MgB2 cores in the obtained MgB2 wires were investigated by XRD and SEM, respectively. Furthermore, the mechanism of SiC doping in MgB2 crystal was simply discussed by TEM observation. The transport Jc values in these wires were measured by four probe method. The optimized sintering temperature was found to be 800 ℃ for 15 min under vacuum condition. The results show that the Jc value of MgB2/Fe wire exceeds 104 A/cm^2 （4.2 K, 11 T）, while the transport Jc value in the 7-MgB2/Nb/Cu/Fe multi-filamentary wire also reaches 104 A/cm^2 （4.2 K, 7.5 T）, which indicating that the multi-filamentary wire could transport current under lower field due to their slightly better thermal stability.

关 键 词：MgB2线材 连续管线成型技术 SIC掺杂 

分 类 号：TM26[一般工业技术—材料科学与工程]