Abstract In this work we investigate the magnetocaloric effect (MCE) in the multicomponent RCo2-type compounds with a Laves phase structure varied by substitutions within both the rare earth (R) and Co sublattices. Complex substitutions increase dramatically the Curie temperatures at which the maximum MCE is observed. The Tbx(Dy0.5Ho0.5)1-xCo2 (0 ≤ x ≤ 0.5) compounds have transitions of the first order at the Curie temperature (TC) and exhibit a large magnetocaloric effect (with the adiabatic temperature change ΔTad as a measure of the effect) decreasing linearly from ΔTad = 3.6 K to 2.2 K (at μ0ΔH = 1.8 T) as x varies between 0 and 0.5. At the increasing Tb concentrations x above 0.5, the transition at TC in Tbx(Dy0.5Ho0.5)1-xCo2 changes order from first to the second while MCE remains constant ∼2.2 K. Volume magnetostriction is of the order of 1000 ppm in Tbx(Dy0.5Ho0.5)1-xCo2 in the vicinity of TC. Sets of compounds Tbx(Dy0.5Ho0.5)1-xCo1.75T0.25 (T = Fe, Al) having equal MCE values, appreciable magnetostrictive strains and continuously increased TC are found.

中文翻译：

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具有不同成分的多组分 Laves 相化合物中磁热效应的持续值

摘要 在这项工作中，我们研究了具有 Laves 相结构的多组分 RCo2 型化合物的磁热效应 (MCE)，这些化合物随稀土 (R) 和 Co 亚晶格内的取代而变化。复杂的取代显着增加了观察到最大 MCE 的居里温度。Tbx(Dy0.5Ho0.5)1-xCo2 (0 ≤ x ≤ 0.5) 化合物在居里温度 (TC) 处具有一阶跃迁并表现出很大的磁热效应（绝热温度变化 ΔTad 作为测量效应）随着 x 在 0 和 0.5 之间变化，从 ΔTad = 3.6 K 线性下降到 2.2 K（在 μ0ΔH = 1.8 T）。当 Tb 浓度 x 增加到 0.5 以上时，Tbx(Dy0.5Ho0.5)1-xCo2 中 TC 处的转变从第一到第二改变顺序，而 MCE 保持恒定~2.2 K。TC 附近的 Tbx(Dy0.5Ho0.5)1-xCo2 中的体积磁致伸缩约为 1000 ppm。发现了具有相同 MCE 值、明显磁致伸缩应变和持续增加的 TC 的化合物 Tbx(Dy0.5Ho0.5)1-xCo1.75T0.25 (T = Fe, Al) 组。