HDDR过程中三元和多元Nd-Fe-B合金磁畴结构的MFM研究

用磁力显微镜研究了三元Nd-Fe-B合金在HDDR过程的不同阶段(铸态、不充分吸氢歧化、充分吸氢歧化和脱氢再复合)的破畴结构。在铸态样品表面清楚地观察到了易磁化轴互相垂直的柱状晶表面的两类磁畴图型。当样品不充分吸氢歧化和充分吸氢歧化时，破畴结构明显发生变化，反映了Nd-Fe-B的分解产物NdH2，α-Fe和Fe2B及其微晶结构的变化。脱氢再复合后形成的微晶的磁畴结构则表明样品保留了铸态样品柱状晶的构型。此外，还对比研究了多元Nd-Fe-B合金在HDDR过程中的磁畴结构，并根据微磁结构分析，指出过量的Ga元素添加可抑制Nd2(Fe，M)14B相的吸氢歧化，从而导致相应HDDR粘结磁体性能降低。

Domain Structures of Trinary and Multiple Nd-Fe-B Magnets During HDDR Process by Using MFM

The domain structures of ternary Nd 13 Fe 80 B 7 alloy at different sta ges of HDDR process were studied by using magnetic force microscope. On the as-cast samples, the column-like crystals with easy axis perpendicular to one another are clearly characterized by their different domain patterns. After the insufficient and sufficient HD treatment, obvious changes of domain structure o cc ur, which is related to the variation of composition and crystalline microstruc ture during HD process. And for the samples after sufficient DR process, it is c onfirmed by the detected domain structures that the configuration of the column -like crystals retains. In addition, the domain structures of multiple Nd 13 Fe bal Co 18 B 7 Ga 3Zr 0.1 alloy during HDDR process w ere also studied for comparison. As a result, at the level of magnetic microstru cture, the evidence has been given for the fact that the addition of superfluous Ga element suppresses the hydrogenation and disproportionnation of Nd 2(Fe,M) 14 B phase, leading to the degraded properties of the corresponding HDDR bonded m agnets.