TY - JOUR
T1 - Microstructures and critical current density of filamentary Eu-Ba-Cu-O with Zr and Zn additions
AU - Ban, E.
AU - Ikebe, Y.
AU - Matsuoka, Y.
AU - Nishijima, G.
AU - Watanabe, K.
N1 - Funding Information:
This work was partially supported by the 21st Century COE Program of the Ministry of Education, Culture, Sports, Science and Technology, Japan. Measurement of the transport J c in applied magnetic field was performed at the High Field Laboratory for Superconducting Materials, Institute for Materials Research, Tohoku University.
PY - 2007/10/1
Y1 - 2007/10/1
N2 - The effect of Zr and Zn doping on superconducting properties and microstructures of filamentary Eu-Ba-Cu-O superconductors prepared by a solution spinning method has been investigated. Samples doped with small amounts of Zr and Zn showed relatively high Jc values of around 2 × 104 A cm-2 at 77 K and 0 T, which was two times larger than that of the pure Eu123 filament. The temperature range for the partial melting in reduced oxygen partial pressure obtained the Jc value higher than 104 A cm-2 at 77 K became wider when Zr and Zn were added. From the SEM observation, a small amount of Zr and Zn doping was found to be useful to reduce the size of Eu211 particles, whereas it showed adverse effects on the dispersion of Eu211 particles and compositional homogeneity in a Eu123 matrix. In the case of Zn doping, although sample showed high Jc value larger than 104 A cm-2 at magnetic field lower than 2 T, a Jc value monotonically decreased at above 3 T and superconductivity was disappeared at 11 T. On the contrary, in spite of the fact that a Jc value of sample with 0.5 at.% Zr decreased by applying only a magnetic field of 0.2 T, superconductivity could be maintained up to 17 T at 77 K.
AB - The effect of Zr and Zn doping on superconducting properties and microstructures of filamentary Eu-Ba-Cu-O superconductors prepared by a solution spinning method has been investigated. Samples doped with small amounts of Zr and Zn showed relatively high Jc values of around 2 × 104 A cm-2 at 77 K and 0 T, which was two times larger than that of the pure Eu123 filament. The temperature range for the partial melting in reduced oxygen partial pressure obtained the Jc value higher than 104 A cm-2 at 77 K became wider when Zr and Zn were added. From the SEM observation, a small amount of Zr and Zn doping was found to be useful to reduce the size of Eu211 particles, whereas it showed adverse effects on the dispersion of Eu211 particles and compositional homogeneity in a Eu123 matrix. In the case of Zn doping, although sample showed high Jc value larger than 104 A cm-2 at magnetic field lower than 2 T, a Jc value monotonically decreased at above 3 T and superconductivity was disappeared at 11 T. On the contrary, in spite of the fact that a Jc value of sample with 0.5 at.% Zr decreased by applying only a magnetic field of 0.2 T, superconductivity could be maintained up to 17 T at 77 K.
KW - Critical current density
KW - Eu-Ba-Cu-O
KW - Filamentary superconductor
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U2 - 10.1016/j.physc.2007.03.447
DO - 10.1016/j.physc.2007.03.447
M3 - Article
AN - SCOPUS:34548473850
SN - 0921-4534
VL - 463-465
SP - 554
EP - 558
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
IS - SUPPL.
ER -