R_3(Fe_(1-x)Co_x)_(29-y)Cr_y(R=Gd,Sm)化合物相稳定性研究  

Investigations of phase stability of R_3(Fe_(1-x)Co_x)_(29-y)Cr_y(R=Gd,Sm) compounds

作　　者：王文全[1] 苏峰[1] 刘春杰[1] 王学凤[1] 闫羽[1] 金汉民[1] 

机构地区：[1]吉林大学物理学院

出　　处：《物理学报》2003年第10期2508-2513,共6页Acta Physica Sinica

基　　金：吉林大学青年教师基金资助的课题~~

摘　　要：在制备出Gd3 (Fe1 -xCox) 2 9-yCry 化合物基础上 ,成功制备出Sm3 (Fe1 -xCox) 2 9-yCry 化合物 ,通过x射线衍射和热磁分析对R3 (Fe1 -xCox) 2 9-yCry(R =Gd ,Sm)化合物相稳定性进行了研究 ,利用原子半径的几何因素解释了高Co含量 3 :2 9型化合物必须要有较多稳定元素的原因 .对于不同的稳定元素 ,稳定元素半径越大 ,所需稳定元素含量越少 ,可是稳定元素的半径愈大 ,其增大晶格常数的能力愈强 ,这反而不利于稳定 3 :2 9相 .通过对R3 (Fe1 -xCox) 2 9-yCry(R =Gd ,Sm)化合物相稳定性的研究 ,成功地制备出具有室温单轴磁晶各向异性的Gd3 (Fe1 -xCox) 2 9-yCry(0 4≤x≤ 1 0 ;4 0≤y≤ 6 5)及新的Sm3 (Fe1 -xCox) 2 9-yCry(0 4≤x≤ 1 0 ;4 5≤y≤ 7 5)化合物 .After the Gd-3(Fe1-xCox)(29-y)Cr-y compound was formed, Sm-3(Fe1-xCox)(29-y)Cr-y compounds were also successfully fabricated. Phase stability of R-3(Fe1-xCox)(29-y)Cr-y(R = Gd, Sm) compounds was investigated by x-ray diffraction and magnetic measurements. Atomic radius theory was employed to interpret why the 3:29 compounds with high Co component had to contain more stabilizing elements. Less stabilizing elements are needed for those with larger atomic radius. However, a large atom of a stabilizing element augments the lattice parameter of the compound, which is disadvantageous to the stability of the 3:29 phase. By studying the phase stability of R-3(Fe1-xCox)(29-y)Cr-y(R = Gd, Sm) compounds, we have fabricated the Crd(3)(Fe1-x Co-x)(29-y)Cr-y(0.4 less than or equal to x less than or equal to 1.0; 4.0 less than or equal to y less than or equal to 6.5) and Sm-3(Fe1-xCox)(29-y)Cr-y(0.4 less than or equal to x less than or equal to 1.0; 4.5 less than or equal to y less than or equal to 7.5) compounds with room-temperature uniaxial magnetocrystalline anisotropy.

关 键 词：R3(Fe1-xCox)29-yCry(R=Gd Sm)化合物 相结构 相稳定性 单轴磁晶各向异性 稀土永磁材料 稀土-铁基金属间化合物 

分 类 号：O482.5[理学—固体物理]