Fabrication and superconducting properties of nano-SiC doped MgB_2 tapes  

作　　者：ZHANG XianPing MA YanWei GAO ZhaoShun YU ZhengGuang WANG DongLiang WATANABE K GUO JianDong 

机构地区：[1]Applied Superconductivity Laboratory, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100080, China [2]Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan [3]Department of Physics, Peking University, Beijing 100080, China

出　　处：《Chinese Science Bulletin》2007年第18期2477-2480,共4页

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos.50472063 and 50377040) ;the State Key Development Program for Basic Re-search Program of China (Grant No. 2006CB601004)

摘　　要：Nano-SiC doped MgB2 tapes were prepared by the in situ powder-in-tube method. Heat treatment was performed at 650℃ for 1 h. XRD data indicate that SiC particles had reacted with the MgB2 during sintering process. MgB2 core seemed to be denser after SiC doping, and the critical temperature was slightly depressed. The critical current density Jc of the SiC doped tapes was significantly enhanced in magnetic fields up to 14 T compared to the undoped ones. For the 5% SiC doped samples, Jc was in- creased by a factor of 32 at 4.2 K, 10 T. The enhancement of Jc-B properties in SiC doped MgB2 tapes is considered to be due to the enhancement of grain linkages and the introduction of effective flux pining centers. The substitution of B by C in MgB2 grains is thought to be the main reason for the improve- ment of the flux pinning ability in SiC doped MgB2 tapes.Nano-SiC doped MgB2 tapes were prepared by the in situ powder-in-tube method. Heat treatment was performed at 650℃ for 1 h. XRD data indicate that SiC particles had reacted with the MgB2 during sintering process. MgB2 core seemed to be denser after SiC doping, and the critical temperature was slightly depressed. The critical current density Jc of the SiC doped tapes was significantly enhanced in magnetic fields up to 14 T compared to the undoped ones. For the 5% SiC doped samples, Jc was increased by a factor of 32 at 4.2 K, 10 T. The enhancement of Jc-B properties in SiC doped MgB2 tapes is considered to be due to the enhancement of grain linkages and the introduction of effective flux pining centers. The substitution of B by C in MgB2 grains is thought to be the main reason for the improvement of the flux pinning ability in SiC doped MgB2 tapes.

关 键 词：硼化镁 纳米碳化硅 临界电流 超导电性 

分 类 号：O511[理学—低温物理]