Tb_(0．3)Dy_(0．7)(Fe_(1-x)Al_x)_(1．95)合金的磁性、磁致伸缩和Mssbauer  

A study of the magnetism, magnetostriction and Mssbauer of Tb_(0.3)Dy_(0.7)(Fe_(1-x)Al_x)_(1.95) alloys

作　　者：郑小平[1] 张佩峰[2] 李发伸[3] 成昭华[4] 沈保根[4] 

机构地区：[1]兰州城市学院 电子信息科学与技术研究所,甘肃兰州730070 [2]兰州大学 计算数学博士后流动站,甘肃兰州730000 [3]兰州大学 磁学与磁性材料教育部重点实验室,甘肃兰州730000 [4]中国科学院物理研究所磁学国家重点实验室,北京100080

出　　处：《兰州大学学报（自然科学版）》2007年第3期101-105,共5页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金(10574059);兰州交通大学"青蓝"人才工程计划;光电技术与智能控制教育部重点实验室开放基金(K040101);中国博士后科学基金资助项目.

摘　　要：系统研究了室温下Tb0．3Dy0．7(Fe1-xAlx)1.95(x=0,0．05,0．1,0．15,0．2,0．25,0．3,0．35)合金中金属Al替代Fe对磁性、磁致伸缩、自旋重取向和穆斯堡尔谱的影响．结果发现,x<0．4时,Tb0．3Dy0．7 (Fe1-xAlx)1.95完全保持MgCu2立方Laves相结构．磁化强度和磁致伸缩测量发现,x<0．15时,添加少量Al有助于减小磁晶各向异性,并且随着Al替代量x增加,磁致伸缩λs、内禀磁致伸缩λ111和Curie温度Tc大幅度降低．多功能磁性测量系统PPMS的研究和Mossbauer效应表明,Tb0．3Dy0．7(Fe1-xAlx)1．95合金的易磁化方向随成分和温度在{110}面逐渐偏离了立方晶体的主对称轴,即自旋重取向．室温下,当x=0．15时,Tb0．3Dy0．7(Fe1-xAlx)1．95合金中出现了少量非磁性相;x>0．15时,该合金完全呈顺磁性;而77K温度下x=0．2时合金仍然呈磁性相．The effect of Al substitution for Fe on the magnetic and magnetostrictive properties, the spin reorientation and Mossbauer spectra of a series of Tb0.3Dy0.7（Fe1-xAlx）1.95 alloys （x=0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35） at room temperature and 77 K has been systemically investigated. It was found that the primary phase of Tb0.3Dy0.7（Fe1-xAlx）1.95 is the MgCu2-type cubic laves phase structure when x 〈 0.4. The magnetization and magnetostriction measurements showed that a small amount of Al substitution is beneficial to a decrease in the magneto crystalline anisotropy for x 〈 0.15, and that the magnetostriction, the spontaneous magnetostriction λ111 and the Curie temperature Tc decrease greatly. The study of PPMS and MSssbauer indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorlentation. A small amount of non-magnetic phase exists for x = 0.15 in Tb0.3Dy0.7（Fe1-xAlx）1.95 alloys and the alloys become paramagnetic for x 〉 0.15 at room temperture, but at 77 K the alloys still remain in magnetic phase even for x = 0.2.

关 键 词：磁致伸缩 立方Laves相 自旋重取向 磁晶各向异性 

分 类 号：O481.4[理学—固体物理] O482.54[理学—物理]