Fe-Cu-Nb-Si-B薄带的淬态纳米化与巨磁阻抗效应

Nano-Crystallization and Giant Magnetoimpedance Effect in Fe-Cu-Nb-Si-B As-Cast Ribbons

使用较低的快淬速度(V =2 2m·s- 1 ) ,可以使Fe Cu Nb Si B薄带实现淬态纳米晶化。Fe Cu Nb Si B薄带析出αFe(Si)纳米相,其晶粒尺寸在淬态薄带Fe73Cu1 .5Nb3Si1 3.5B9中约为15nm ,在Fe71 .5Cu3Nb3Si1 3.5B9中约为10nm。添加Cu元素可以细化淬态薄带的晶粒。实验发现磁阻抗ΔZ/Z0 ,磁电阻ΔR/R0 ,磁电抗ΔX/X0 三条曲线交叉于一点,通过推导发现此现象具有必然性。淬态薄带Fe74 .5-xCuxNb3Si1 3.5B9的磁阻抗显示了较强的Cu含量依赖性。在快淬速度v =2 2m·s- 1 下,在x =1.5和x =3左右观察到磁阻抗峰值现象。

Nano-crystallization in as-cast ribbons Fe-Cu-Nb-Si-B can be obtained with lower quenching speed. Under quenching speed of 22 m·s -1 , bcc α-Fe(Si) phase precipitates in Fe_ 74.5-x Cu_xNb_3Si_ 13.5 B_9 ribbons with grain size of 15 nm for x=1.5 and 10 nm for x=3. The addition of Cu refines the grain size of Fe_ 74.5-x Cu_xNb_3Si_ 13.5 B_9 as-cast ribbons. It shows that curves of frequency dependence of magnetoimpedance, magnetoresistance and magnetoreactance intersect at a certain frequency inevitably. The magnetoimpedance of Fe_ 74.5-x Cu_xNb_3Si_ 13.5 B_9 as-cast ribbons strongly depends on the Cu content. Under quenching speed of 22 m·s -1 , the magnetoimpedance peaks can be found at x=1 5 and x=3 0 for Fe_ 74.5-x Cu_xNb_3Si_ 13.5 B_9 as-cast ribbons.