驱动场对铁基纳米晶条带的LDGMI效应影响研究

发布时间：2018-04-01 15:32

本文选题：纵向驱动的巨磁阻抗效应　切入点：驱动场　出处：《华东师范大学》2017年硕士论文

【摘要】：近年来,软磁材料GMI(Giant Magnetoimpedance effect)效应因其灵敏度高、体积小、功耗低等优点成为研发弱磁传感器的主要方法之一,引起国内外广泛关注。目前驱动场对GMI效应影响的研究主要采用传统的四探针法测量模式。但存在磁材料焊接和材料受焦耳热影响的问题,使驱动场大小受到限制。本文采用纵向驱动方式来研究Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9纳米晶条带的GMI效应。同时,分析了不同片数纳米晶条带的磁滞回线变化特点,以及驱动场和纳米晶条带片数对样品的LDGMI效应、感应电压波形和谐波分布的影响,主要结论如下:(1)发现随着Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9纳米晶条带片数的增加,因相邻条带间存在磁偶极相互作用。样品的各向异性场和饱和磁化强度均线性地增加,矫顽力近乎为零,磁结构更加偏横向。(2)低驱动场下不同片数纳米晶条带的LDGMI曲线形状均为"小平台",且"平台"宽度受驱动场大小、频率的调制。同时,因条带间存在磁偶极相互作用,样品的"平台"宽度和各向异性场均随条带片数的增多而线性增加;(3)不同的样品在高驱动场下均会发生非线性磁化,其LDGMI曲线均表现为"大平台"。当交变驱动场的增强时,各向异性场小的样品非线性磁化的程度高,相同条件下样品的LDGMI曲线"平台"展宽。同时,不同样品在相同驱动场下的频谱曲线形状不同,各向异性场小的样品特征频率易向高频移动,究其原因是样品在相同条件下非线性磁化程度不同造成的。
[Abstract]:In recent years, the soft magnetic material GMI(Giant Magnetoimpedance effecteffect has become one of the main methods for developing weak magnetic sensors because of its high sensitivity, small size and low power consumption. At present, the influence of driving field on GMI effect is mainly studied by traditional four-probe method. However, there are some problems in magnetic material welding and Joule heat effect. The size of driving field is limited. The GMI effect of Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9 nanocrystalline strip is studied by longitudinal driving method. At the same time, the characteristics of hysteresis loop of nanocrystalline strip with different number of chips are analyzed. The effects of driving field and the number of nanocrystalline strips on the LDGMI effect, induced voltage waveform and harmonic distribution of the samples are also discussed. The main conclusions are as follows: 1) it is found that with the increase of the number of Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9 nanocrystalline strips, Due to the magnetic dipole interaction between adjacent bands, the anisotropic field and saturation magnetization of the sample increase linearly, and the coercivity is near zero. The shape of LDGMI curve of nanocrystalline strips with different number of slices is "small platform", and the width of "platform" is modulated by the driving field size and frequency. At the same time, because of the magnetic dipole interaction between the strips, Both the "platform" width and the anisotropic field of the sample increase linearly with the increase of the number of strips. The samples with different samples have nonlinear magnetization under high driving field, and their LDGMI curves are all shown as "large platforms". When the alternating driving field increases, The nonlinear magnetization of the sample with small anisotropic field is high, and the LDGMI curve "platform" of the sample is widened under the same conditions. At the same time, the shape of the spectrum curve is different for different samples under the same driving field. The characteristic frequency of the sample with small anisotropic field is easy to move to high frequency, which is caused by the different nonlinear magnetization degree of the sample under the same condition.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.1

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