TY - JOUR
T1 - Microstructure in high-density MgB2 wires prepared by an internal Mg diffusion method
AU - Shimada, Yusuke
AU - Kubota, Yuuki
AU - Hata, Satoshi
AU - Ikeda, Ken Ichi
AU - Nakashima, Hideharu
AU - Matsumoto, Akiyoshi
AU - Togano, Kazumasa
AU - Hur, Jahmahn
AU - Kumakura, Hiroaki
N1 - Funding Information:
Manuscript received August 03, 2010; accepted November 01, 2010. Date of publication November 22, 2010; date of current version May 27, 2011. This work was supported in part by Nanotechnology Support Project of the Ministry of Education, Culture, Sport, Science, and Technology (MEXT) and Grants-in-Aid from MEXT and in part by the Japan society for the Promotion of Science, Japan.
PY - 2011/6
Y1 - 2011/6
N2 - Several reaction-induced diffusion processes to fabricate high-density MgB2 materials are developed, and the critical current density (Jc) has been notably enhanced. In this study, microstructure in high-density MgB2 wires fabricated by an internal Mg diffusion (IMD) process has been investigated. The inner reacted region of the wire heat-treated at 640 °C for 1 h shows dense polycrystalline MgB2 of 20-200 nm in grain sizes. Fine MgO and Mg2Si particles of 10-30 nm in sizes are dispersed in this region. On the other hand, the outer region near the Ta sheath is composed of unreacted B and SiC powders, fine MgO particles and small voids. Sizes of voids in the IMD MgB2 wire are small compared with the PIT MgB2 wire. Oxidation of Mg in the IMD process forms fine dispersion of MgO which may be effective for flux pinning.
AB - Several reaction-induced diffusion processes to fabricate high-density MgB2 materials are developed, and the critical current density (Jc) has been notably enhanced. In this study, microstructure in high-density MgB2 wires fabricated by an internal Mg diffusion (IMD) process has been investigated. The inner reacted region of the wire heat-treated at 640 °C for 1 h shows dense polycrystalline MgB2 of 20-200 nm in grain sizes. Fine MgO and Mg2Si particles of 10-30 nm in sizes are dispersed in this region. On the other hand, the outer region near the Ta sheath is composed of unreacted B and SiC powders, fine MgO particles and small voids. Sizes of voids in the IMD MgB2 wire are small compared with the PIT MgB2 wire. Oxidation of Mg in the IMD process forms fine dispersion of MgO which may be effective for flux pinning.
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U2 - 10.1109/TASC.2010.2091097
DO - 10.1109/TASC.2010.2091097
M3 - Article
AN - SCOPUS:79957946516
SN - 1051-8223
VL - 21
SP - 2668
EP - 2671
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
IS - 3 PART 3
M1 - 5643189
ER -