低温应力退火Fe基合金薄带巨磁阻抗特性的研究

Study on giant magneto-impedance characteristics of Fe-based alloy ribbons under low temperature stress annealing

通过同步辐射X射线衍射技术,观测Fe73.5Cu1Nb3Si13.5B9非晶薄带经过不同温度和不同应力退火60 min后样品的微观结构,利用HP4294A型阻抗分析仪测量相应样品的巨磁阻抗比与磁各向异性。研究结果表明,在450℃下施加不同应力退火的样品仍然处于非晶结构状态,并且在应力为112.1 MPa的条件下产生优异的磁性能,样品的最大巨磁阻抗比达到了1818.7%,是自由退火条件下最大巨磁阻抗比的1.9倍,同时能够改变巨磁阻抗曲线的形状,使Fe基合金薄带的巨磁阻抗曲线具有宽线性的特性。对实验数据进行拟合后发现,样品的最大巨磁阻抗比和磁各向异性场与外加应力都具有线性关系,磁感灵敏度与外加应力具有负指数关系。通过探究发现具有非晶结构的Fe基合金薄带的磁学性能对应力敏感,可以作为研究非晶纳米晶合金材料应力敏感问题的另一个新方向。

In this paper,the microstructure of Fe73.5Cu1Nb3Si13.5B9 amorphous ribbons annealed at different temperature and different stress for 60 min was observed by the synchrotron radiation technique.The giant magneto-impedance ratio and magnetic anisotropy of the corresponding samples were measured by HP4294A impedance analyzer.The results show that under the condition that the annealing temperature was lower than the glass-transition temperature of FeCuNbSiB,the samples were still amorphous which annealed under different stress,and the shape of giant magneto-impedance curve had changed and the wide linear property had appeared.When the stress was 112.1 MPa,the maximum giant magneto-impedance ratio of the sample reached 1818.7%,which was 1.9 times higher than that under free annealing.After fitting the experimental data,it was found that the maximum giant magneto-impedance ratio and magnetic anisotropy field of the sample were linearly related to the applied stress,and the magnetic inductance sensitivity had a negative exponential relationship with the applied stress.It was found that the magnetic properties of Fe-based alloy ribbons with amorphous structure were sensitive to stress,which could be used as another new direction to study the stress sensitivity of amorphous nanocrystal alloy materials.