化学镀CoP/Insulator/BeCu复合结构丝的巨磁阻抗效应研究

Investigation of giant magneto-impedance effect in electroless-deposited CoP/Insulator/BeCu wires

采用含复合络合剂的碱性镀液,改变镀液配方组分和工艺条件在绝缘层上合成软磁性良好的CoP合金镀层,制备出CoP/Insulator/BeCu复合结构的巨磁阻抗效应材料。样品采用电流退火进行焦耳热处理。电流退火后,在较低频率下观察到显著的磁阻抗效应,在97kHz时最大磁阻抗效应为991%,磁场灵敏度高达2.78%/(A.m-1);在3kHz^30MHz的频率范围内,磁阻抗比率都在50%以上,具有很宽的频率应用范围。利用复数磁导率探讨材料的磁化特性,发现有效磁导率实部和虚部的频率特性在退火后发生了很大变化。

By controlling the process conditions the CoP/Insulator/BeCu composite wires with distinct giant magneto-impedance effect （GMI） have been prepared by electroless-deposition on polyester-coated BeCu wires. The as-deposited sample was treated with current annealing. A dramatic increase of the GMI value was observed at a low frequency after current annealing. The maximum GMI ratio reaches about 991% and the field sensitivity amounts to 2.78%（A · m^-1 ） at 97kHz. The GMI value is above 50% at the frequency range from 3kHz to 30MHz. The properties of magnetization processes for the annealed samples are analyzed via the complex permeability. The real and imaginary part of the complex permeability change significantly with the variation of DC magnetic field after current annealing.