电流退火对CoFeSiB非晶丝和薄带的巨磁阻抗效应比较

Comparison between CoFeSiB Amorphous Wires and Ribbons after Joule Annealing on Magnetoimpedance Effect

采用熔融抽拉法和单辊急冷法分别制备了Co68.25Fe4.5Si12.25B15非晶丝和薄带。测量了制备态下两者的巨磁阻抗(GMI)效应,发现非晶丝的GMI比率高于薄带。研究了不同电流密度退火后非晶丝和薄带的GMI效应,结果发现ΔΖ/Ζ=[Z(H)-Z(H=0)]/Z(H=0)都明显上升,且非晶薄带数值更大;当电流密度等于0.96×107A/m2时,薄带的这一比率最大达到410%,磁场灵敏度达到5.1%/(A/m)。分析了出现上述现象的原因。

Co68.25Fe4.5S12.25B15amorphous wires and ribbons are produced by melt-extraction method and single roller melt spinning method, respectively. After measuring the GMI effect of them in as-quenched state, it is found that the GMI ratio of wire is higher than that of ribbon. The relationship between GMI effect and the density of annealing current is investigated, and as a result, the ratios,△Z/Z=[Z（H）-Z（H=0）]/Z（H=0）, of both wires and ribbons rise obviously and the values of amorphous ribbons are higher. When the current density is 0. 96 × 10^7 A/m^2 , this maximal GMI ratio of ribbon can reach about 410%, the sensitivity of magnetic field achieves 5. 1%/（A/m）. The possible reason for these phenomena is discussed.