软磁薄带巨磁阻抗效应的数值分析

NUMERICAL STUDY ON GIANT MAGNETO IMPEDANCE EFFECTS IN SOFT MAGNETIC RIBBONS

利用磁畴壁移动模型以纳米晶软磁合金Ｆｅ７３．５Ｃｕ１Ｎｂ３Ｓｉ１３．５Ｂ９为例对软磁薄带中的巨磁阻抗效应进行了数值分析，结果发现不同的磁导率机制并不能显著改变巨磁阻抗效应，巨磁阻抗效应的大小仅由磁导率对外加磁场的敏感性决定。从趋肤深度的角度讨论了巨磁阻抗效应的频率特性，只有当趋肤深度和薄带的半厚度相当时才产生显著的巨磁阻抗效应，材料的磁导率增大、电阻率降低或样品的厚度增加能使巨磁阻抗效应向低频端移动。

Using the model of magnetic domain walls movement the giant magneto impedance (GMI) effects in soft magnetic ribbons were studied numerically in this paper It was found that the mechanism of permeability has little effects on GMI The magnitude of GMI was determined by the field sensitivity of permeability, the larger the change of permeability with the external magnetic field, the larger the GMI effects With the reduction of resistivity, or the increase of permeability and thickness of the sample the GMI effects would shift to low frequency range and it was explained by the skin depth dependence of GMI effects