Abstract

The effect of substitution of yttrium for thulium in the Tm(Co_0.84Fe_0.16)₂ compound on the crystal structure, temperature and field dependences of magnetization (σ), temperature dependences of the high-field susceptibility (χ_hf), isothermal magnetic entropy change (∆S_m), and adiabatic temperature change (∆T_ad) is studied. The magnetic and magnetocaloric properties were measured in magnetic fields up to 90 kOe in a temperature range of 5–380 K. The dependences σ(T) measured in an external magnetic field of 100 Oe were found to exhibit the magnetization inversion. The field dependence of the magnetic moment of the Tm_0.4Y_0.6(Co_0.84Fe_0.16)₂ compound, which is measured at 5 K, exhibits a point of inflection corresponding to a magnetic field of 49.5 kOe; the substantial increase in the magnetic field leads to an increase in the susceptibility of the sample to the magnetic field. Samples characterized by magnetic compensation temperature demonstrate the alternation of direct and inverse magnetocaloric effect (MCE). A number of the compounds under study exhibit the plateau-like temperature dependences of ∆S_m and ∆T_ad in a temperature range of inverse MCE. The results obtained are discussed.

中文翻译：

---

Tm1 – xYx(Co0.84Fe0.16)2 化合物的磁性和磁热特性

摘要

_{Tm(Co 0.84} Fe _0.16 ) ₂化合物中钇替代铥对晶体结构、磁化强度(σ)的温度和场依赖性、高场磁化率(χ _hf )的温度依赖性、等温磁熵的影响变化（Δ S _m）和绝热温度变化（Δ T _ad）进行了研究。在 5-380 K 的温度范围内，在高达 90 kOe 的磁场中测量了磁性和磁热特性。发现在 100 Oe 的外部磁场中测量的相关性 σ( T ) 表现出磁化反转。_{Tm 0.4}的磁矩的场依赖性Y _0.6 (Co _0.84 Fe _0.16 ) ₂化合物，在5 K下测得，显示出对应于49.5 kOe磁场的拐点；磁场的显着增加导致样品对磁场的敏感性增加。以磁补偿温度为特征的样品展示了直接和反向磁热效应 (MCE) 的交替。许多正在研究的化合物在逆 MCE 的温度范围内表现出 Δ S _m和 Δ T _ad的平台状温度依赖性。讨论了获得的结果。