电流退火对CoFeSiB非晶丝和薄带的巨磁阻抗效应比较

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。

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

Co_(68.25)Fe_(4.5)Si_(12.25)B_(15) amorphous 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(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.