掺杂Sn对(La,Ce)(Fe,Al,Si)_(13)合金磁热效应和相变性质的影响  

Effect of Sn Doping on Magnetocaloric Effect and Phase Transition Properties of(La,Ce)(Fe,Al,Si)_(13)Alloys

作　　者：宋博宇 韩永全[1,3] 程娟[4] 高磊 刘翠兰 黄焦宏 Song Boyu;Han Yongquan;Cheng Juan;Gao Lei;Liu Cuilan;Huang Jiaohong(Inner Mongolia University of Technology,Hohhot 010051,China;Baotou Vocational and Technical College,Baotou 014030,China;Engineering Research Center of Development and Processing Protection of Advanced Light Metals,Ministry of Education,Hohhot 010051,China;State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization,Baotou 014030,China)

机构地区：[1]内蒙古工业大学,内蒙古呼和浩特010051 [2]包头职业技术学院,内蒙古包头014030 [3]先进轻金属材料开发与加工防护教育部工程研究中心,内蒙古呼和浩特010051 [4]白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古包头014030

出　　处：《稀有金属材料与工程》2023年第7期2335-2342,共8页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(52066001);Science and Technology Plan Project of Inner Mongolia Autonomous Region(2020GG0313);Inner Mongolia Natural Science(2021MS05016);Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region of China(NJZY22119);Northern Rare Earth Project(BFXT-2021-D-0013)。

摘　　要：研究了磁制冷材料La_(0.75)Ce_(0.25)Fe_(11.5-x)Al_(0.2)Si_(1.3)Sn_(x)(x=0,0.05,0.1,0.2)的磁热效应和相变性质。X射线衍射结果表明,随着Sn掺杂浓度的增加,主相1:13相减少,α-Fe和LaFeSi相增加。引入密度泛函理论,结合实验结果得出,增加Sn掺杂浓度能够增大晶格常数,并增强相邻原子之间的交换相互作用,从而提高居里温度。当磁场变化为2 T时,体系中最大磁熵变为13.59 J·kg^(-1)·K^(-1),其相对制冷能力为154 J/kg,具有成为磁制冷材料的潜力。通过Banerjee准则和等温熵变的场相关指数n确定当Sn掺杂浓度为0.05%(质量分数)时,合金由一级相变转变为二级相变。合金的相变行为对Sn含量非常敏感,可以通过调节Sn掺杂浓度,实现多级串联制冷。The magnetocaloric effect and phase transition properties of La_(0.75)Ce_(0.25)Fe_(11.5-x)Al_(0.2)Si_(1.3)Sn_(x)(x=0,0.05,0.1,0.2,wt%)alloys were investigated.X-ray diffraction results show that with increasing the Sn doping content,the content of 1:13 main phase is decreased,and the content ofα-Fe and LaFeSi phases is increased.By combining the density functional theory with experimental results,it is found that increasing the Sn doping content can increase the lattice constant and enhance the exchange interactions between adjacent atoms,thereby increasing the Curie temperature.When the magnetic field is 2 T,the maximum magnetic entropy change in the system is 13.59 J·kg^(-1)·K^(-1)and its relative cooling power is 154 J/kg,showing great potential as magnetic refrigeration material.Based on the Banerjee criterion and the field dependence index n of isothermal entropy change,it is concluded that when the Sn doping content is 0.05wt%,the first-order phase transition changes to the second-order phase transition of the alloy.The phase transition behavior of the alloy is very sensitive to the Sn content,and multi-stage series refrigeration can be achieved by adjusting the doping content.

关 键 词：磁热效应 LaFeSi 相变 

分 类 号：TB64[一般工业技术—制冷工程] TG132[一般工业技术—材料科学与工程]