【摘要】 通过TEM和HRTEM对比研究了软磁层厚度为2.5 um的Nd₂Fe₁₄B/α-Fe型多层膜的显微结构.结果表明,在退火前的多层膜中Fe层为多晶,硬磁相以非晶的状态存在;在600℃以上退火后软磁层消失,生成的Nd₂Fe₁₄B型相被固定在硬磁层内;625℃退火后发现有Nd₂Fe₁₇相在硬磁层中析出,表明在多层膜退火过程中,退火温度对相转变的影响比退火时间的影响更大.Nd₂Fe₁₇相的析出可能是高温退火后磁性能下降的主要原因.更多还原

【Abstract】 Microstructure of Nd₂Fe₁₄B/α-Fe-type multilayer films annealed at 600℃ for 5min and annealed at 625℃ for 1 min with the same thickness of α-Fe layers （2.5 nm） have beeninvestigated by TEM and HRTEM. The result showed that α-Fe nano-grains formed in Fe layers in theas-sputtered film. however. the hard magnetic phase remained amorphous state. When the annealingtemperature was higher than 600℃, Nd₂Fe₁₄B type phases formed, the α-Fe layers were devouredby the hard magnetic layers, and Nd₂Fe₁₇ phases were found in another multilayer film annealedat 625℃. It implied that the annealing temperature played a more important role in the phasetransformation than the annealing time. The decrease of magnetic properties maybe resulted from theseparating out of Nd₂Fe₁₇ phase.更多还原