Tb_(0.3)Dy_(0.7-x)Pr_x(Fe_(0.9)Al_(0.1))_(1.95)合金的磁致伸缩、自旋重取向和穆斯堡尔谱研究  

Magetostriction,spin reorientation and Mssbauer effect studies of Tb_(0.3)Dy_(0.7-x)Pr_x(Fe_(0.9)Al_(0.1))_(1.95) alloys

作　　者：郑小平[1] 张佩峰[2] 范多旺[2] 李发伸[3] 郝远[4] 

机构地区：[1]兰州城市学院电子信息科学与技术研究所,兰州730070 [2]兰州交通大学光电技术与智能控制教育部重点实验室,兰州730070 [3]兰州大学磁学与磁性材料教育部重点实验室,兰州730000 [4]兰州理工大学甘肃省有色金属新材料重点实验室,兰州730050

出　　处：《物理学报》2007年第1期535-540,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10574059);甘肃省自然科学基金(批准号:3ZSO42-B25-033);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(编号:K040101);中国博士后科学基金资助的课题~~

摘　　要：系统研究了室温下Tb0·3Dy0·7-xPrx(Fe0·9Al0·1)1·95(x=0,0·1,0·2,0·25,0·3,0·35)合金中稀土元素Pr替代Dy对晶体结构、磁致伸缩、各向异性和自旋重取向的影响.结果发现,x≤0·1时,Tb0·3Dy0·7-xPrx(Fe0·9Al0·1)1·95完全保持MgCl2立方Laves相结构,0·1<x≤0·3,有杂相出现并且随Pr替代量逐渐增多;晶格常数a随Pr含量x的增加缓慢增大.磁致伸缩测量发现,随着替代量x的增多磁致伸缩减小;x>0·2时超磁致伸缩效应消失.然而,x=0·1时合金的磁致伸缩略大于没有替代的,而且磁致伸缩随磁场更易趋于饱和,说明Pr替代有助于降低磁晶各向异性.内禀磁致伸缩λ111随Pr替代量x的增加接近线性增加.由相对磁化率随温度的变化关系可以看出,自旋重取向温度随Pr替代量的增多呈先增后降趋势,在x=0·1处出现极大值.穆斯堡尔效应表明,随Pr含量的增加Tb0·3Dy0·7-xPrx(Fe0·9Al0·1)1·95合金中易磁化轴可能在{110}面上绕主对称轴作微小转动,发生自旋重取向.与Al元素替代效应相比,Pr替代Dy对自旋重取向的影响相对较小.The effect of Pr substitution for Dy on the structure, rnagnetostriction, anisotropy and spin reorientation of a series of Tb0.3Dy0.7-xPrx（Fe0.9Al0.1）1.95 alloys （x =0, 0.1, 0.20, 0.25, 0.30, 0.35） at room temperature has been investigated. It was found that the Tb0.3Dy0.7-xPrx（Fe0.9Al0.1）1.95substantially retained the MgCu2-typo C-15 cubic Laves phase structure for compositions with x ≤0.1 and the lattice constant increases slowly with increasing x. The magnetostriction of the Tb0.3Dy0.7-xPrx（Fe0.9Al0.1）1.95 alloys decreases drastically with increasing x and the magnetostrictive effect disappears for x 〉 0.2. However, the magnetostriction shows a slightly bigger value at x = 0.1 than the free alloys and is saturated more easily with the magnetic field H, showing that a small amount of Pr substitution is beneficial to the decrease in the magnetocrystalline anisotropy. The spontaneous magnetostriction 2m increases linearly with incresasing x, whereas ＇the spin reorientation temperature increases first and then decreases rapidly. The analysis of the Moessbauer spectra indicated that the easy magnetization direction in the { 110} plane deviates slightly from the main axis of symmetry with the increase in Pr concentration x, namely the spin reofientation. Compared with the Al substitution, the effect of Pr substitution for Dy on the spin reorientation is smaller.

关 键 词：磁致伸缩 立方Laves相 自旋重取向 穆斯堡尔谱 

分 类 号：O482.5[理学—固体物理]