论文部分内容阅读
测量了不同晶粒尺寸的纳米晶Ni_3Fe和Fe_(75)Al(12.5)Ge_(12.5)的磁化曲线。这些材料是通过高能球磨接着在不同温度下退火制成。之所以选择这两种成份,是因为它们的大块材料具有低的磁致伸缩。这意味着样品中的应变对磁性的影响很小。利用M-H磁化曲线得到矫顽力、最大磁导率和饱和磁化强度。这些磁性能的差异和晶粒尺寸及均方根(RMS)内应变(平均有效应变)的变化有关。尽管这两种大块材料的磁致伸缩小,内应力还是控制着矫顽力。但是,磁导率的变化并不象从晶粒尺寸变化趋势所预料的那样。我们提出的看法是,粉末的形态在决定这两种纳米晶合金的软磁性能中起重要作用。
The magnetization curves of nanocrystalline Ni_3Fe and Fe_ (75) Al (12.5) Ge_ (12.5) with different grain sizes were measured. These materials are made by high-energy ball milling followed by annealing at different temperatures. The reason for choosing these two components is because their bulk material has a low magnetostriction. This means that the strain in the sample has little effect on magnetism. The coercive force, the maximum permeability and the saturation magnetization were obtained by using M-H magnetization curve. The differences in these magnetic properties are related to the grain size and the change in root mean square (RMS) strain (mean effective strain). Despite the small magnetostriction of these two bulk materials, the internal stress controls the coercivity. However, the change in permeability is not as expected from the tendency of the grain size to change. Our suggestion is that the morphology of the powder plays an important role in determining the soft magnetic properties of these two nanocrystalline alloys.