纳米复合永磁材料的交换耦合作用和有效各向异性

EXCHANGE-COUPLING INTERACTION AND EFFECTIVE ANISOTROPY IN NANOCOMPOSITE PERMANENT MATERIALS

以Nd2Fe14B／α-Fe为例,对纳米双相永磁材料软、硬磁性相晶粒间的交换耦合作用和有效各向异性进行了模型化计 算,得到软、硬磁性相晶粒间的有效各向异性常数随晶粒尺寸和软磁性相比例的变化关系曲线.结果表明,交换耦合部分采用6种 不同函数计算,得到的有效各向异性随晶粒尺寸的变化曲线几乎重合.有效各向异性常数随晶粒尺寸的减小逐渐减小,随软磁性相 比例的减小逐渐增大.

The exchange-coupling interaction between magnetically soft and hard grains in nanocomposite Nd2Fe14B/alpha-Fe and their effects on the effective anisotropy of materials have been investigated. By testing six different functions, series of curves of effective anisotropy constant versus grain size and volume fraction of the soft phase were obtained. The calculated results show that the effective anisotropy constant decreases with the reduction of grain size and increases with the decrease of the volume fraction of the soft phase. The calculated curves resemble the experimental results.