CeFe_(2-x)In_x合金磁性研究与CeFe_(1.95)In_(0.05)合金磁相变临界参数分析  

Magnetic property of CeFe_(2-x)In_x alloys and critical parameters of magnetic phase transition of CeFe_(1.95)In_(0.05) alloy

作　　者：陈湘[1,2] 赵明骅 Chen Xiang;Zhao Ming-Hua(College of Physics and Electronic Information Engineering,Neijiang Normal University,Neijiang 641100,china;The Ames Laboratory,U.S.Department of Energy,Iowa State University Ames,Iowa 50011-3020,USA)

机构地区：[1]内江师范学院物理与电子信息工程学院,内江641112 [2]The Ames Laboratory,U.S. Department of Energy,Iowa State University

出　　处：《物理学报》2018年第19期275-285,共11页Acta Physica Sinica

基　　金：四川省科技厅科研基金(批准号:2017JY0181);四川省教育厅科研基金(批准号:16ZB0301)资助的课题~~

摘　　要：通过等温磁化曲线和等磁场变温曲线测量与标度理论,系统研究了CeFe_(2-x)In_x合金的磁性和CeFe_(1.95)In_(0.05)合金的磁相变临界参数.结果表明:用2.5 at.%的铟替代CeFe_2合金中的铁并不能使合金中的反铁磁态在低温下完全稳定,低场下在2—80 K均能观察到反铁磁相振荡; CeFe_2与CeFe_(1.95)In_(0.05)合金的顺磁-铁磁二级相变居里温度均在230 K附近;在0—5 T磁场范围内, CeFe_(1.95)In_(0.05)合金居里温度处的最大磁熵变为3.13 J/(kg·K),相对制冷量为151.3 J/kg.通过不同方法得到的具有高度自洽性的磁相变标度临界参数均表明CeFe_(1.95)In_(0.05)合金的磁相互作用可以用基于短程相互作用的3D-Ising模型来描述.Magnetic properties of CeFe（2-x）Inx alloys and scaling critical behaviors of CeFe（1.95）In（0.05） alloy are investigated by measuring the magnetic susceptibility and isothermal magneteization. The X-ray diffraction（XRD） patterns show that the solid solubility of the In substituted for the Fe in CeFe（2-x）Inx alloy is limited. Because the intensity diffraction peak of impurity at 2θ = 30.75？and 35.80？in CeFe（1.95）In（0.05） XRD pattern are very low, the effect of impurity on magnetism is not considered in this paper. Magnetic measurements indicate that using 2.5 at.% indium to substitute for Fe in CeFe2 alloy can strengthen the orbital hybridization interaction between Ce-4f and Fe-3d, but it cannot reach the critical point to make the antiferromagnetic stable. The AFM fluctuation still keeps in a value ranging from 2 K to 80 K. The second order paramagnetic-ferromagnetic transition of CeFe（1.95）In（0.05） at TC= 230 K is confirmed by Arrott plot analysis. The effective ferromagnetic moment of Fe atoms can be increased by replacing part of the Fe atoms with In atoms in the CeFe2 alloy, which can increase the paramagnetic and effective magnetic moment and the magnetic saturation magnetic moment of the alloy. For a magnetic field change of 0–50 kOe, the maximum value of the magnetic entropy change-？SM is 3.13 J/（kg·K） at 230 K and RCP is 151.3 J/kg, which are higher than the values of Ce（0.95）Gd（0.05）Fe2, Ce（0.9）Gd（0.1）Fe2,and Ce（0.9）Ho（0.1）Fe2 alloys under the same magnetic field. The high self-consistent scaling critical exponents determined by modified Arrott plot and Kouvel-Fisher methods are [β = 0.3212（8） and γ = 0.9357（9）] and [β = 0.3304（1） andγ = 0.9249（1）], respectively. The parameter δ obtained from the critical magnetization isotherm M（TC）= DH^（1/δ） satisfies the Widom scaling relation δ = 1 ＋ γ/β. Moreover, the plot of M^（1/β） vs.（H/M）^（1/γ） constructed by the above critical parameters com

关 键 词：CeFe1.95In0.05合金 磁热性能 标度理论 临界参数 

分 类 号：TG132.27[一般工业技术—材料科学与工程]