Shang Tao, Zheng Lin, Zhao Jianjun, Li Guodong, Wu Ruixia
Department of Physics Science and Technology, Baotou Teacher's College, Baotou 014030, China.
Department of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China.
Materials (Basel). 2022 Feb 20;15(4):1589. doi: 10.3390/ma15041589.
The arc-melting method was adopted to prepare the compound LaPr(FeCo)Si ( = 0, 0.02, 0.04, 0.06, 0.08), and the magnetocaloric effect of the compound was investigated. As indicated by the powder X-ray diffraction (XRD) results, after receiving 7-day high temperature annealing at 1373 K, all the compounds formed a single-phase cubic NaZn crystal structure. As indicated by the magnetic measurement, the most significant magnetic entropy change |∆()| of the sample decreased from 28.92 J/kg·K to 4.22 J/kg·K with the increase of the Co content under the 0-1.5 T magnetic field, while the Curie temperature increased from 185 K to the room temperature 296 K, which indicated that this series of alloys are the room temperature magnetic refrigerant material with practical value. By using the ferromagnetic Curie temperature theory and analyzing the effect of Co doping on the exchange integral of these alloys, the mechanism that the Curie temperature of LaPr(FeCo)Si and LaCe(FeCo)Si increased with the increase in the Co content was reasonably explained. Accordingly, this paper can provide a theoretical reference for subsequent studies.
采用电弧熔炼法制备了化合物LaPr(FeCo)Si（= 0, 0.02, 0.04, 0.06, 0.08），并对该化合物的磁热效应进行了研究。粉末X射线衍射（XRD）结果表明，在1373 K下进行7天高温退火后，所有化合物均形成单相立方NaZn晶体结构。磁测量结果表明，在0 - 1.5 T磁场下，随着Co含量的增加，样品的最大磁熵变|∆( )|从28.92 J/kg·K降至4.22 J/kg·K，而居里温度 从185 K升高至室温296 K，这表明该系列合金是具有实用价值的室温磁制冷材料。利用铁磁居里温度理论并分析Co掺杂对这些合金交换积分的影响，合理地解释了LaPr(FeCo)Si和LaCe(FeCo)Si的居里温度随Co含量增加而升高的机理。据此，本文可为后续研究提供理论参考。
