Tb_(0.3)Dy_(0.7)(Fe_(1-x)Al_x)_(1.95)合金的自旋重取向和穆斯堡尔

Spin reorientation and Msbauer effect studies on Tb_(0.3)Dy_(0.7)(Fe_( 1-x)Al_x)_(1.95) alloys

系统研究了室温和 77K温度时Tb0 3Dy0 7(Fe1 -xAlx) 1 95(x =0 ,0 0 5 ,0 1,0 15 ,0 2 ,0 2 5 ,0 3,0 35 )合金中金属Al替代Fe对自旋重取向和穆斯堡尔谱的影响 .结果发现 ,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 ,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 .在室温和 77K温度时 ,超精细场Hhf均随Al元素的增加而减小 ,而同质异能移IS 随Al元素的增加而增加 ,四极劈裂QS 随Al含量呈无规律的变化 .

The effect of Al substitution for Fe on the spin reorientation and Mssbauer sp ectra of a series of Tb 0.3Dy 0.7(Fe 1-xAl x) 1.95 alloys (x=0.05,0.1,0.15,0.20,0.25,0.30,0.35) at room tempera ture and 77K has been investigated systematically. The results indicate that the easy magnetization direction in the {100} plane deviates slightly from the main axis of symmetry, namely spin rerioentation. A small amount of non_magnetic pha se exists for x=0\^15, and the alloys become paramagnetism when x>0\^15 at room temperture, but at 77K the alloys still remain to be magnetic phase even at x=0\^2. At room temperature and 77K, the hyperfine field decreases and t he isomer shift increases with increasing concentration of Al, and the quaduple splitting Q S shows weak concentration dependence.