晶粒尺寸在很大程度上决定了Fe基纳米晶合金的磁学性能,其随退火温度变化的物理机理是纳米晶领域重要的研究内容.研究了初始晶化温度与二次晶化温度之间退火1hFe基纳米晶合金晶粒尺寸随退火温度的变化,并建立了相应的模型.利用提出的模型分析了该温度范围内Fe基纳米晶合金晶粒尺寸随退火温度升高先减小后增大的物理机制.研究发现,在初始晶化温度与二次晶化温度之间等时退火,当退火温度约为Fe基纳米晶合金熔点的0.6倍时其晶粒尺寸最小.在研究的温度区间内,理论研究结果与实验符合得较好.本研究提供了一种快速获得小晶粒尺寸纳米晶合金的方法.
The magnetic properties of the Fe-based nanocrystalline alloys are determined mainly by their grain sizes, and the mechanism of the variation of grain size with annealing temperature is an important issue in the study of nanocrystalline alloys. In this paper, the relationships between grain size and annealing temperature for these alloys within the primary crystallization temperature (Tχ1) and the secondary crystallization temperature (Tχ2) for I h are investigated, and a corresponding model is proposed. The physical mechanism of the fact that the grain size first decreases and then increases with the increase of annealing temperature is explained by using this model. It is found that the grain size has a minimum value when these alloys are isochronally annealed at the temperature near 0.6 times that of the melting point. Theoretical analysis results are found to be in agreement with the experiments data within the investigated temperature range. This investigation provides a means to obtain the smallest grain size quickly.