烧结NdFeB铸造新工艺-薄片铸锭法

Novel casting technique in manufacture of NdFeB sintered magnets strip casting

合金铸造技术是制备高性能烧结NdFeB磁体的关键工艺之一 .根据高性能磁体制造的设计要求 ,NdFeB合金铸锭微观组织应该具有柱状晶完整 ,没有α -Fe偏析相 ,富钕相弥散分布的特点 .本文比较了现有几种生产中常用的铸造方法 -平板铸造、柱状铸造、薄板铸造等得到的合金铸锭 ,然后介绍了目前国际上高性能NdFeB磁体制备的铸造新工艺 -薄片铸锭法 ,并通过扫描电镜观察了不同Nd含量薄片铸锭的组织结构 .最后展望了薄片铸锭在我国的应用前景 .

The casting technique is important in manufacture of high performance NdFeB sintered magnets. The ideal ingots have the following microstructure characteristics: homogeneous fine columnar grains, free dendritic α-Fe, good dispersion of rare earth rich phase without aliquation. The common techniques employed nowadays in factories were reviewed such as plate casting, column casting and thin plate casting. Novel technique strip casting used to produce high performance sintered magnets in the world was introduced. Microstrure of the samples fabricated by strip casting with different compositions of Nd were observed via SEM. The future of the application of strip casting in production was discussed.