講演情報
[24a-12P-2]Activated Densification of Ba0.6K0.4Fe2As2 Bulk Superconductor by Yttrium Addition
〇(M2)Nur Rahmawati Ayukaryana1, Shota Ishiwata1, Akiyasu Yamamoto1 (1.Tokyo Univ. A&T)
キーワード：
Fe-based superconductor、Metal addition、Spark plasma sintering
Ba0.6K0.4Fe2As2 belongs to the iron-based superconductor family in which superconductivity is induced by K element substitution in Ba site. Doping of K in BaFe2As2 (K-Ba122) demonstrated high critical temperature up to 38 K [1], extraordinary upper critical field Hc2 value of 50-100 T and irreversibility field Hirr value of >50 T, and large critical grain boundary angle (8°-9°) [2]. On the other hand, further structural investigation to improve the critical current density (Jc) of Ba122 superconductors is required to achieve practical application competitiveness.
In this study, the addition of 2mol% yttrium is investigated. Previously, a high-energy milling optimization experiment was conducted, and the resulting optimized condition was employed here [3][4]. K-Ba122 bulk was synthesized by SPS (Spark Plasma Sintering) method [5]. As exhibited in Fig. 1, yttrium can activate densification by shifting the bulk displacement rate peak to lower temperature by 200℃. Fig. 2 shows that Ba122 was obtained as the main phase. Moreover, yttrium peak is not detected in the XRD pattern, suggesting a possibility of substitution into the lattice. The microstructural observation and superconducting properties measurement will be reported.
In this study, the addition of 2mol% yttrium is investigated. Previously, a high-energy milling optimization experiment was conducted, and the resulting optimized condition was employed here [3][4]. K-Ba122 bulk was synthesized by SPS (Spark Plasma Sintering) method [5]. As exhibited in Fig. 1, yttrium can activate densification by shifting the bulk displacement rate peak to lower temperature by 200℃. Fig. 2 shows that Ba122 was obtained as the main phase. Moreover, yttrium peak is not detected in the XRD pattern, suggesting a possibility of substitution into the lattice. The microstructural observation and superconducting properties measurement will be reported.