The isothermal section of the Ho–Fe–In system at 773 K has been constructed by X-ray powder diffraction. One known structure ternary compound Er12Fe2In3-type Ho12Fe2In3 has been confirmed. At the same time, solid solutions are not detected in Ho–Fe–In system at 773 K. The magnetic transition and magnetocaloric effect of Ho12Fe2.08In2.92 alloy with Er12Fe2In3-type structure were investigated by magnetic susceptibility and isothermal magnetization measurements. One normal antiferromagnetic–paramagnetic transition and another abnormal one are discovered at 18 and 76 K in ground state, respectively. Owing to a first-order field-induced metamagnetic transition (antiferromagnetic–ferromagnetic) at/below the Néel temperature of 18 K), the negative entropy changes are observed at corresponding temperature. There is only a second-order ferromagnetic–paramagnetic transition near Curie temperature (TC), the maximum entropy change (ΔSmax\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \Delta S_{ {\rm max} } $$\end{document}) values are − 6.14 J·kg−1·K−1 at 3 K and 7.88 J·kg−1·K−1 at 28 K in a field range of 0–7 T. The reversible relative cooling power corresponding to negative entropy change can reach about 600 J·kg−1 in an wide operating temperature region ΔTcycl\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \Delta T_{\text{cycl}} $$\end{document} = 74 K from 16 to 90 K, which suggests that Ho12Fe2.08In2.92 could be a potential material for magnetic refrigeration in the corresponding temperature range.

中文翻译：

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Ho-Fe-In 在 773 K 的实验等温截面相图和 Ho12Fe2.08In2.92 合金的磁性能

通过 X 射线粉末衍射构建了 Ho-Fe-In 系统在 773 K 的等温截面。一种已知结构的三元化合物 Er12Fe2In3 型 Ho12Fe2In3 已被证实。同时，在 773 K 的 Ho-Fe-In 系统中未检测到固溶体。通过磁化率和等温磁化强度测量研究了具有 Er12Fe2In3 型结构的 Ho12Fe2.08In2.92 合金的磁转变和磁热效应。分别在基态 18 K 和 76 K 处发现了一个正常的反铁磁-顺磁跃迁和另一个异常的跃迁。由于在 18 K Néel 温度/低于 Néel 温度时发生一阶场诱导变磁转变（反铁磁-铁磁），在相应温度下观察到负熵变化。