中国物理B ›› 2015, Vol. 24 ›› Issue (7): 77503-077503.doi: 10.1088/1674-1056/24/7/077503
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
何春a b c, 张明晓a b, 邵艳艳a b, 董京杜a b, 闫阿儒a b, 刘剑a b
He Chun (何春)a b c, Zhang Ming-Xiao (张明晓)a b, Shao Yan-Yan (邵艳艳)a b, Dong Jing-Du (董京杜)a b, Yan A-Ru (闫阿儒)a b, Liu Jian (刘剑)a b
摘要: In the present work we reported the phase formation, microstructure, magnetocaloric effect and hydrogenation behavior of La-rich La1.7Fe11.6Si1.4 alloy. In this off-stoichiometric La(Fe,Si)13 alloy, the NaZn13-type La(Fe,Si)13 matrix phase shows faceted grains, with the Cr5B3-type La5Si3 used as the secondary phase distributed intergranularly. Such a peculiar morphology quickly forms upon one day annealing. In La1.7Fe11.6Si1.4 alloy, we have observed a significant field dependence of magnetostructural transition temperature (~ 6.3 K/T), resulting in a large and table-like entropy change (ΔS~ 18 J/kg·K in 2 T) over a broad temperature range (~ 10 K). Upon hydrogenation, the maximum value of ΔS keeps almost unchanged, while the Curie temperature increases up to 350 K. These results indicate that the investigated off-stoichiometric La(Fe,Si)13 alloy is a promising magnetic material for magnetic refrigerators.
中图分类号: (Intrinsic properties of magnetically ordered materials)