Effect of boron particle size on microstructure and superconducting properties of in-situ Cu addition MgB2 multifilamentary wire

11th European Conference on Applied Superconductivity

Hishinuma, Y.^1 ; Kikuchi, A.^2 ; Shimada, Y.^3 ; Hata, S.^3 ; Takeuchi, T.^2 ; Yamada, S.^1 ; Sagara, A.^1

National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu

509-5292, Japan^1

National Institute for Materials Science, 1-2-1 Sengen, Ibaraki, Tsukuba

305-0047, Japan^2

Kyusyu University, 6-1 Kasugakoen, Kasuga, Fukuoka

816-8580, Japan^3

关键词: Average particle size;    Boron particle;    Critical transition temperatures;    Fine particles;    Microstructure control;    Milling time;    Multifilamentary wire;    Superconducting properties;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/2/022009/pdf
DOI  :  10.1088/1742-6596/507/2/022009

来源: IOP

【 摘 要 】

In previous studies, the secondary (impurity and non-reactive) phase and voids were observed in MgB2matrix after the heat treatment, and then these are the lowering factors of critical current density (Jc) property. In order to improve Jcproperty by microstructure control of MgB2matrix, the fine elemental boron powder as the raw material was carried out using the high-speed vibrated milling with tungsten carbide (WC) jar. The average particle size of metal boron powder was decreased from 1.14 μm to 0.20 μm by the high-speed vibrated milling. The various fine particle boron powders as the function of milling time were also prepared, and in-situ Cu addition MgB2multifilamentary wires using these fine boron powders were fabricated. Critical transition temperature (Tc) value of Cu addition MgB2wire using fine boron powder obtained to about 37 K. No change of the Tcproperty by the different particle sized boron powders was confirmed. In this paper, the comparisons of microstructure and superconducting properties between the different boron particle sizes were investigated.