Fe84Zr3.5Nb3.5B8Cu1薄带的动态磁化过程

由于铁磁性样品的交流磁化率虚部χ″随磁场强度H的变化是非线性的，在低场(0～12 mT)有一个与铁磁共振信号强度相当的低场非共振信号. 利用ESR谱仪测量交流磁化率虚部χ″对磁场强度H的一次微分随磁场强度的变化dχ″/dH～H，研究Fe₈₄Zr_3.5Nb_3.5B₈Cu₁合金薄带的动态磁化特性. 合金薄带样品是各向异性的，易磁化轴（易轴）在薄带的横向方向，外加磁场H在易轴方向. 样品在可逆磁化区域(0～2.0 mT)和趋近饱和的磁化区域(9.0 mT以上)，dχ″/dH=0；在不可逆畴壁移动过程中，当H为4.2 mT 时, χ″(H)达到最大值χ_max；在磁畴转动过程中，χ″(H)正比于H²（瑞利区）；而实验中却发现，在某些区域交流磁化率虚部χ″(H) 与磁场强度H的n次方即Hⁿ(n≥3)有关；而且发现，在一定区域，有三段不可逆畴壁移动和磁畴转动交替出现的现象. 在这一过程中，dχ″/dH为常数的磁场范围分别为4.8～5.2mT, 5.8～6.4 mT, 8.0～8.5 mT, 其常数相对值分别为1：0.85：0.60. 样品的交流磁化率虚部χ″对磁场H的微分dχ″/dH随磁场H的这一变化规律反映了不可逆畴壁移动和磁畴转动交替发生的微观过程.

THE DYNAMIC MAGNETIC PROCESS OF Fe84Zr3.5Nb3.5B8Cu1 RIBBON

Since the χ″ non-linearly changes following the magnetic field H in the ferromagnetic sample, there is a low field (0～12 mT) non-resonance signal having a comparable strength with that of the ferromagnetic resonance signal. With the ESR spectrometer, the change dχ″/dH]～H is measured，and then study dynamicmagnetization of the alloy ribbon Fe₈₄Zr_3.5Nb_3.5B₈Cu₁. The sample of alloy ribbon is anisotropic, the easy (magnetization) axis of thesample is in the lateral direction of the ribbons, and the H is at this direction. It is found that dχ″/dH=0 in the regions of the reversible (0～2.0mT) and saturation magnetization (≥9.0 mT). When the domain wall motion is nonreversible,the χ″(H) is the largest value χ_max when the H is 4.2 mT. And χ″is relevant to H² during the domain rotation (Rayleigh region). It is found however in the experiment that the χ″(H) being in proportion to H² and Hⁿ(n≥3) are alternatively formed in three sections. During this process, the magnetic fields that the dχ″/dH is constants are 4.8～5.2 mT, 5.8～6.4 mT and 8.0～8.5 mT respectively. The macroscopic phenomenon, that dχ″/dH equals non-zero constant or not alternatively is a microscopic demonstration that domain wall motion and domain rotation.