Transmission electron microscopy analysis of C4H4S-doped MgB2 tapes

N Yuzuriha, H Sosiati, S Hata, N Kuwano, H Yamada, N Uchiyama, A Matsumoto, H Kitaguchi, H Kumakura
2008 Journal of Physics, Conference Series  
Critical current anisotropy of MgB 2 tapes P Ková -Simulation and electrical characterization of MgB 2 and YBCO tapes for superconducting fault current limiter prototypes R Dalessandro, M Bocchi, V Rossi et al. -Comparative study of different chemical doping effect on the J c -B properties of MgB 2 tapes X Zhang, Y Ma, Z Gao et al. -Recent citations Imperfection of microstructural control in MgB2 superconducting tapes fabricated using an in-situ powder-in-tube process: toward practical
more » ... ons S. Hata et al -This content was downloaded from IP address 207.241.231.83 on 01/05 Abstract. It has been reported that doping with aromatic hydrocarbons in an in situ powder-intube fabrication process of MgB 2 tapes is effective for increasing the critical current density (J c ) under magnetic fields. In this study, the mechanism of the J c enhancement by doping with C 4 H 4 S was investigated by transmission electron microscopy (TEM). The C 4 H 4 S-doped MgB 2 tape has a denser cross-sectional microstructure than that of a non-doped MgB 2 tape. Electron diffraction and dark-field TEM observation indicated that the grains of MgB 2 are well crystallized and slightly increase in size with the C 4 H 4 S doping. X-ray diffraction and twodimensional elemental mapping using characteristic x-rays suggested that C atoms substitute part of B atoms in MgB 2 crystals. Unlike other kinds of impurity doping, such as SiC-doping, there were few nanosized inclusions formed by C 4 H 4 S doping. Thus, it is concluded that the J c enhancement with the C 4 H 4 S doping is due to (i) increasing supercurrent and magnetic-flux pinning at grain boundaries by the formation of dense and well-crystallized MgB 2 matrix and (ii) increasing the upper critical field by the formation of Mg(B,C) 2 .
doi:10.1088/1742-6596/97/1/012277 fatcat:qlvgd5cydfds3eqexknf4cs5nu