共查询到19条相似文献,搜索用时 49 毫秒
1.
对Co基熔体抽拉非晶丝进行了普通炉内退火和不同磁场强度(500 Oe,1600 Oe,4000 Oe)下的横向和纵向磁场退火,利用HP4192阻抗分析仪和Lakeshore7407VSM分析了退火态样品的巨磁阻抗(GMI)效应和软磁性能.研究结果表明,纵向磁场降低了环向各向异性,纵向磁场退火样品GMI效应降低且GMI曲线为单峰,最大阻抗变化率ΔZ/Z为131%,磁场响应灵敏度为7%/Oe;而横向磁场提高了环向畴体积,增加了环向各向异性场,导致退火样品GMI曲线随频率升高由单峰转
关键词:
非晶丝
巨磁阻抗效应
退火 相似文献
2.
3.
本文研究了交流电流的大小(I =0.2—20 mA)和频率(f = 1—1 MHz)对具有横向畴结构的铁基纳米晶丝的巨磁阻抗效应形貌的影响.实验结果表明,样品的巨磁阻抗效应呈双峰特征,随着频率的增大,双峰的位置H=±Hm向高场移动;但随着电流的增大,双峰的位置逐渐向中心(H = 0)收缩,甚至变成单峰位形.理论上一般认为,双峰的位置与横向各向异性场Hk相对应,即H<
关键词:
巨磁阻抗效应
交流电流
铁基纳米晶丝 相似文献
4.
新一类磁传感效应——巨磁阻抗效应 总被引:2,自引:0,他引:2
材料的交流阻抗随外加直流磁的改变而变化的特性称为磁阻抗效应,在软磁合金中,这种效应是快响应,高灵敏度的,因而被称为巨磁阻抗效应,文章简单介绍了这一效应产生的基本原理、高频和低频交流电流情况下这一效应的特点,介绍了这一效应的应用前景。 相似文献
5.
6.
7.
8.
材料的交流阻抗随外加直流磁场的改变而变化的特性称为磁阻抗效应.在软磁合金中,这种效应是快响应、高灵敏度的,因而被称为巨磁阻抗效应.文章简单介绍了这一效应产生的基本原理、高频和低频交流电流情况下这一效应的特点,介绍了这一效应的应用前景 相似文献
9.
研究了Fe36Co36Nb4Si4.8B19.2合金薄带为磁芯的螺线管(FeCo基磁芯螺线管)的巨磁阻抗效应与磁芯长度之间的关系.研究结果表明,磁芯长度是影响FeCo基磁芯螺线管巨磁阻抗效应的重要因素.当磁芯长度小于螺线管长度时,磁芯螺线管巨磁阻抗的最大值(ΔZ/Z)max与磁芯长度呈线性关系,其线性相关系数可以根据电磁学理论推导得到;当磁芯的长度大于螺线管的长度时,由于漏磁作用,(ΔZ/Z)max与磁芯长度的关系偏离了线性关系,(ΔZ/Z)max与磁芯长度的关系曲线中有一个极值点,(ΔZ/Z)max在极值点达到最大.磁芯螺线管巨磁阻抗效应曲线的尖刺部分高度(ΔZ/Z)T与磁芯长度的关系也有类似的极值点,(ΔZ/Z)T在极值点达到最大值.磁芯螺线管巨磁阻抗效应曲线的尖刺部分对弱磁场敏感,受磁芯退磁场的影响明显,磁芯的退磁场与磁芯长度呈负指数关系.
关键词:
磁芯螺线管
FeCo基合金薄带
巨磁阻抗效应
磁芯长度 相似文献
10.
采用层间胶合方法制备了淬态非晶FeSiB/Cu/FeSiB三明治薄带,研究了同尺寸单层薄带和三明治薄带的巨磁阻抗(giant magneto-impedance, GMI)随外磁场与带轴夹角β的变化特性.结果表明,FeSiB单层薄带在7.0 MHz最佳响应频率下,GMI仅约30%,外磁场与带轴夹角对单层薄带GMI几乎没有影响;三明治薄带的GMI效应则十分显著,在0.6 MHz最佳响应频率下,纵、横向GMI比分别达到272%和464%, GMI随β的增大而增强;所有β角的三明治薄带GMI曲线都出现各向异性峰,各向异性峰随β的增大而展宽.根据磁畴转动模型推导了薄带横向磁导率与各向异性场及β之间的函数关系式.结果显示,三明治薄带GMI随夹角β变化的特性与理论推算的横向磁导率变化有较好的一致性,而单层薄带则不然.该磁畴转动模型能定性解释三明治薄带GMI随外磁场方向变化特性. 相似文献
11.
The microstructure of CosoNi22Ga28 ribbon with the L10 structure is examined. The band-like morphology is observed. These bands with the width in a range of 40-200 nm appear along the transverse direction of the ribbon. The giant magnetoimpedance (GMI) effect in this alloy is measured. The results show that Co5oNi22Ga28 exhibits a sharp peak of the GAI effect. The maximum GAH ratio up to 360% is detected. The GMI effect measured versus temperature shows large jumps of the magnetoimpedance amplitude at the reversal martensitic transformation temperature 240℃ and Curie temperature 375℃C respectively. The jump ratios of the magnetoimpedance amplitude examined at these temperatures are about 5 and 10, respectively. 相似文献
12.
Effects of Slight Plastic Deformation on Magnetic Properties and Giant Magnetoimpedance of FeCoCrSiB Amorphous Ribbons 下载免费PDF全文
S. O. Volchkov M. A. Cerdeira V. V. Gubernatorov E. I. Duhan A. P. Potapov V. A. Lukshina 《中国物理快报》2007,24(5):1357-1360
Slight plastic deformation of 0 to 1% by cold rolling is proposed as a treatment which may modify the responses of magnetoimpedance (MI) sensor with an amorphous ribbon used as a sensitive element. The dependence of the magnetic properties of melt spun Fe3Co67Cr3Si15B12 amorphous ribbons and their MI responses in the initial state and after slight plastic deformation on the value of the deformation were comparatively analysed. The shape of the hysteresis loops shows a clear correlation with the value of the deformation. The variations of the total impedance, the real and the imaginary components, are measured for the current intensity of 1.S mA for the frequency of lO MHz. Slight plastic deformation affects both real and imaginary components and allows a control of the shape of the MI curves in a small field in a range usually used in biomedical applications. The proposed deformation treatments can be useful for the construction of the MI sensitive elements with a new type of the responses. 相似文献
13.
14.
Partha Sarkar 《Journal of magnetism and magnetic materials》2010,322(8):1026-1031
The giant magneto-impedance of melt spun CoxFe72−xNb4Si4B20(x=10, 20, 36, 50) amorphous and nanostructured ribbons have been investigated. Alloys have been optimized at the driving current amplitude, frequency and found that amorphous ribbon of nominal composition of Co36Fe36Nb4Si4B20 shown maximum GMI ratio of 13%. The behaviour of the driving current amplitude on the GMI behaviour was studied and the sample was optimized for driving current amplitude, Iac=10 mA. The frequency dependence of the GMI behaviour was studied for the ribbon sample Co36Fe36Nb4Si4B20 at frequency in the range of 100 kHz-1.2 MHz of the optimized driving current amplitude and it was found that the sample showed the maximum GMI behaviour at f=700 kHz. The optimized samples were Joule heated at the current density J=0-35 A/m2 for a period of 1 min. The GMI ratio initially increased then progressively deteriorated with J, but after a certain range it shows up to 16% of improvement in the magneto-impedance value due the increase of nanocrystalline volume fraction. The asymmetry in the GMI profile was observed for the sample Joule heated at J=1-5 A/m2 for 1 min. 相似文献
15.
Ferromagnetic Antiresonance and Giant Microwave Magneto-Impedance in Polycrystalline La0.49Sr0.51MnO3 下载免费PDF全文
The ferromagnetic antiresonance (FMAR) phenomenon, i.e., the minimum of the microwave absorption, in polycrystalline La0.49Sr0.51MnO3 is observed near Curie temperature TC = 282 K. Temperature-dependences of magnetization μ0M are obtained from the FMAR. The results show that as μ0H = 0, by fitting the scaling law M ∝ (TC -T)^β to temperature-dependences of μ0M at the different microwave frequencies, it yields TC=281.2 K and β = 0.47. However, temperature-dependences of μ0M under different μ0H are not in agreement with the scaling law. Due to FMAR, about 40% giant microwave magneto-impedance at 11.9 GHz can occur under a low field μ0H = 0.03 T. 相似文献
16.
B.Y. Hu J.X. Yang G. Chen G.T. Shen K.Y. Jiang X.L. Yang G. Zhang 《Hyperfine Interactions》1998,112(1-4):107-110
The magneto-impedance effect in Fe-based nanocrystalline Fe73Cu1Nb1.5Mo2Si13.5B9 alloys has been observed. The results showed that the field dependence of the MI ratio was strongly influenced by the transverse
magnetic structure in samples, which was demonstrated by Moessbauer spectroscopy.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
The application of FINEMET-type materials with specific magnetic properties prepared by the crystallization of amorphous alloys is often limited by their brittleness. The structure of these materials consists of nanosized Fe-based grains surrounded by an amorphous phase. Then the final macroscopic mechanical properties are considerably influenced by the properties of this amorphous phase. Direct creep measurements during the crystallization of FINEMET alloys were performed and the creep properties of the residual amorphous phase formed during the nanocrystallization were described. It was shown that due to relatively high temperatures, the residual amorphous phase undergoes intensive structural relaxation resulting in the obvious embrittlement of these materials. 相似文献
18.
19.
We built electron and phonon free energies and attempted to investigate the effect of the electron-phonon interaction on giant magnetoresistance in magnetic multilayers. Starting from a jellium-like model, we found that the electron-phonon interaction can have an important effect on the spin splitting of electronic energy band. The expression of giant magnetoresistance has been obtained by considering the spin splitting of electronic energy band,indicating that the effect of phonon could not be neglected. Numerical calculations using our approach demonstrate the agreement between experimental and theoretical values. 相似文献