三维碳负载镍掺杂对MgB_(2)微观结构和超导性能的影响  

Effect of three-dimensional carbon supported Ni doping onmicrostructure and superconducting properties of MgB_(2)

作　　者：赵倩 秦保军 平学成 龚闯闯 ZHAO Qian;QIN Baojun;PING Xuecheng;GONG Chuangchuang(Tianjin Key Laboratory of Integrated Design and On-line Monitoring for Light Industry&Food Machinery and Equipment,College of Mechanical Engineering,Tianjin University of Science&Technology,Tianjin 300222,China;Tianjin International Joint Research and Development Center of Low-Carbon Green Process Equipment,Tianjin 300222,China;School of Materials Science&Engineering,Tianjin University,Tianjin 300354,China)

机构地区：[1]天津科技大学机械工程学院天津市轻工与食品工程机械装备集成设计与在线监控重点实验室,天津300222 [2]天津市低碳绿色过程装备国际联合研究中心,天津300222 [3]天津大学材料科学与工程学院,天津300354

出　　处：《功能材料》2022年第8期8009-8016,共8页Journal of Functional Materials

基　　金：国家自然科学基金项目(51975411)。

摘　　要：寻找满意的第三组元并通过简单的化学掺杂获得高性能的MgB_(2)超导体,对推进MgB_(2)的实用化进程有着十分重要的意义。采用盐模板冻干法合成了三维碳(3DC)和三维碳负载镍(3DC/Ni)两种粉末,并通过原位掺杂的方式使用固相烧结法分别制备了含有这两种添加剂的MgB_(2)块材。借助X射线衍射技术及扫描电子显微镜对3DC掺杂MgB_(2)和3DC/Ni掺杂MgB_(2)的物相组成及微观形貌进行了表征,同时结合磁学测量系统探究了两种添加剂对MgB_(2)超导性能的影响。结果表明,3DC可以形成有效的碳掺杂提高MgB_(2)在高场下的载流性能;掺杂3DC/Ni后在Mg-Ni低温液相辅助烧结及3DC提供形核位点的协同作用下改善了MgB_(2)的晶粒连接性,同时也提高了MgB_(2)的磁通钉扎能力。采用冻干法合成的Ni颗粒在纳米尺度,解决了小尺寸掺杂易团聚的问题,但由于Ni为磁性粒子,使3DC/Ni掺杂MgB_(2)的临界电流密度(J_(c))没有明显提高。寻找一种更有效的金属纳米粒子是今后的尝试方向。Finding a satisfactory third component and obtaining high-performance MgB_(2) superconductor through simple chemical doping is of great significance to promote the practical process of MgB_(2).In this paper,three-dimensional carbon(3DC)and three-dimensional carbon supported nickel(3DC/Ni)powders were synthesized by salt template freeze-drying method,and MgB_(2) blocks containing these two additives were prepared by in-situ doping and solid-state sintering.The phase composition and micro morphology of 3DC doped MgB_(2) and 3DC/Ni doped MgB_(2) were characterized by X-ray diffraction and scanning electron microscope.At the same time,the effects of the two additives on the superconductivity of MgB_(2) were investigated combined with magnetic measurement system.The results show that 3DC can form effective carbon doping and improve the current carrying performance of MgB_(2) in high field.After doping 3DC/Ni,under the synergistic effect of Mg-Ni low temperature liquid phase assisted sintering and 3DC providing nucleation sites,the grain connectivity of MgB_(2) and the flux pinning ability of MgB_(2) are improved.In this paper,the Ni particles synthesized by freeze-drying method solve the problem of easy agglomeration of small-size doping in nano scale,but the critical current density(J_(c)) of 3DC/Ni doped MgB_(2) is not significantly improved because Ni is a magnetic particle.Looking for a more effective metal nanoparticles is the direction of attempt in the future.

关 键 词：二硼化镁 原位掺杂 三维碳 临界电流密度 磁通钉扎 

分 类 号：TM262[一般工业技术—材料科学与工程]