Co-based amorphous alloys are often utilized as magnetic core for fluxgate sensor due to their excellent comprehensive performance with eminent permeability and insignificant coercivity. Herein, we investigated the effects of Nb doping on the phase composition, amorphous formation, magnetic domain structure and soft-magnetic characteristics of (CoFeSiB)Nb (x = 0, 1, 3, 5, 7) alloy ribbons and its fluxgate performance. Additionally, related magnetic parameters as magnetic permeability and coercivity of the ribbon under zero magnetic-field annealing (ZFA) as well as longitudinal magnetic-field annealing (LFA) and fluxgate sensitivity and noise value were also tested. It is verified that the Nb doping is well able to optimize their amorphization, thermostability and soft magnetic properties. When x = 3, the ribbon presents the most well-distributed magnetic domain structure and the inferior soft magnetic properties, with an initial permeability of 8900 and a coercivity of 1.51 A/m. Compared with ZFA, LFA is more effective on improving the soft magnetic and fluxgate behavior. The highest of 24,520 and the lowest of 0.18 A/m are obtained at x = 3 for the LFA sample, where the fluxgate sensitivity is up to 44.15 mV/μT, accompanied by the peak-to-peak noise (denoted by Noise) value is as low as 1.38 nT.

中文翻译：

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Nb掺杂对CoFeNbSiB非晶带磁性能及其磁通门行为的影响

钴基非晶合金因其优异的综合性能、较高的磁导率和较小的矫顽力而常被用作磁通门传感器的磁芯。在此，我们研究了Nb掺杂对(CoFeSiB)Nb (x = 0, 1, 3, 5, 7)合金带材的相组成、非晶形成、磁畴结构和软磁特性及其磁通门性能的影响。此外，还测试了零磁场退火（ZFA）和纵向磁场退火（LFA）下薄带的磁导率和矫顽力等相关磁参数以及磁通门灵敏度和噪声值。事实证明，Nb掺杂能够很好地优化其非晶化、热稳定性和软磁性能。当x=3时，薄带呈现最均匀的磁畴结构和较差的软磁性能，初始磁导率为8900，矫顽力为1.51 A/m。与ZFA相比，LFA在改善软磁和磁通门行为方面更有效。 LFA 样品在 x = 3 时获得最高 24,520 A/m 和最低 0.18 A/m，其中磁通门灵敏度高达 44.15 mV/μT，并伴有峰峰值噪声（用“噪声”表示）值低至 1.38 nT。