Er-Y-Cr-Si化合物在极低温区的巨低场磁热效应  

Giant low-field magnetocaloric effect of(Er,Y)Cr_(2)Si_(2)compounds at ultra-low temperatures

作　　者：奚磊 郑新奇 高亚伟 许家旺 刘超凡 王鼎淞 徐菊萍 殷雯 杨淑娴 靳宝杰 朱梦媛 许玮峯 申见昕 张静言 黄河 吴燕飞 顾飞 史慧宇 陶怡璇 王守国 沈保根 Lei Xi;Xinqi Zheng;Yawei Gao;Jiawang Xu;Chaofan Liu;Dingsong Wang;Juping Xu;Wen Yin;Shuxian Yang;Baojie Jin;Mengyuan Zhu;Weifeng Xu;Jianxin Shen;Jingyan Zhang;He Huang;Yanfei Wu;Fei Gu;Huiyu Shi;Yixuan Tao;Shouguo Wang;Baogen Shen(School of Materials Science and Engineering,Beijing Advanced Innovation Center for Materials Genome Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Materials Science and Engineering,Anhui University,Hefei 230601,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences&University of Chinese Academy of Sciences,Beijing 100190,China;Songshan Lake Materials Laboratory,Dongguan 523808,China;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Spallation Neutron Source Science Center,Dongguan 523803,China;Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China)

机构地区：[1]School of Materials Science and Engineering,Beijing Advanced Innovation Center for Materials Genome Engineering,University of Science and Technology Beijing,Beijing 100083,China [2]School of Materials Science and Engineering,Anhui University,Hefei 230601,China [3]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences&University of Chinese Academy of Sciences,Beijing 100190,China [4]Songshan Lake Materials Laboratory,Dongguan 523808,China [5]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [6]Spallation Neutron Source Science Center,Dongguan 523803,China [7]Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China

出　　处：《Science China Materials》2023年第5期2039-2050,共12页中国科学（材料科学（英文版）

基　　金：supported by the National Key Research and Development Program of China(2021YFB3501202 and 2019YFB2005800);the Science Center of the National Science Foundation of China(52088101);the National Natural Science Foundation of China(51871019,52171170,52130103,51961145305,and 51971026);the 111 Project(B170003)。

摘　　要：高性能低温低场磁热材料在气体液化等领域具有重要的应用前景.本团队通过真空电弧熔炼的方式成功合成了一系列多晶Er_(1-x)Y_(x)Cr_(2)Si_(2)(0≤x≤0.8)样品,这些材料表现出巨大的低场磁热效应.其中Cr含量为0.1的样品显示出最好的低场磁热性能以及接近2 K的合适的工作温区.更重要的是,在0-1 T的磁场变化下,该样品的最大磁熵变峰值以及最大绝热温变峰值分别高达19.2 J kg^(-1)K^(-1)和4.3 K.其磁熵变峰值为目前已报道的20 K以下温区合金类磁热材料的最大值.通过Arrott曲线,平均场理论以及约化磁熵变曲线等手段,证明了磁相变特征为二级相变.物理机理分析表明,10%的Y替代导致高达15.9%的磁熵变峰值增强的原因在于替代样品所具有的大饱和磁化强度以及小饱和磁场.Low-temperature and low-field magnetocaloric materials with high magnetocaloric effect(MCE)performance have important prospects in applications such as gas liquefaction.A series of polycrystalline Er_(1−x)Y_(x)Cr_(2)Si_(2)(0≤x≤0.8)samples were successfully synthesized by arc melting,showing giant low-field MCE.For the sample with x=0.1,the compound shows the best MCE performance,with the appropriate working temperature down to 2 K.Furthermore,the maximum value of magnetic entropy change((−ΔS_(M))/_(max))and adiabatic temperature change((Δ_(Tad))_(max))under the field change of 0–1 T are calculated to be 19.2 J kg^(−1) K^(−1) and 4.3 K correspondingly.The value of(−ΔS_(M))_(max) is the largest ever reported for intermetallic MCE materials below 20 K.The characteristic of magnetic phase transition is verified to be of second order on basis of Arrott plots,mean field theory and rescaled universal−ΔS_(M) curves.The physical mechanism indicates that the great enhancement of(−ΔS_(M))_(max) as large as 15.9%due to 10%Y substitution originates from the larger saturation magnetic moments and the smaller saturated magnetic fields.

关 键 词：magnetocaloric effect magnetic structure RCr_(2)Si_(2)compounds 

分 类 号：TB64[一般工业技术—制冷工程]