(西安交通大學材料學院， 西安 710049)
摘 要: 研究了氫化／歧化／脫氫／重組(簡稱HDDR)工藝過程中NdFeCoZrB合金相組成和磁性能的變化規(guī)律。結(jié)果表明，經(jīng)氫化／歧化后合金中除了正常的歧化產(chǎn)物外，還存在少量未分解的Φ 相晶粒殘核；在脫氫／重組過程中，隨著真空中氫氣壓力ps 的降低， 磁粉中重組形成的Φ 相的體積分數(shù)不斷增加，同時粉末粘結(jié)磁體的內(nèi)稟矯頑力線性升高， 磁各向異性值在ps＝60 kPa處出現(xiàn)最大值。分析表明，HDDR粉末的磁各向異性是通過重組過程中Φ 相在殘留晶核處的擇優(yōu)形核形成的，但在較低的ps 下Φ相還發(fā)生了任意形核，并對HDDR粉末磁各向異性的形成具有不利影響。
關鍵字: NdFeB HDDR 顯微組織 磁各向異性
（School of Materials, Xi'an Jiaotong University, Xi'an 710049）
Abstract:Phases and magnetic properties of NdFeCoZrB alloy during the HDDR process were studied. It was found that some residual particles of Φ phase co-exist with decomposed products in the disproportionated alloy. During the desorption-recombination transformations, the volume fraction of recombined Φ phase is increased with decreasing hydrogen pressure ps in vacuum, and intrinsic coercivity of bonded magnets is linearly increased whereas a maximum anisotropy is determined at ps =60 kPa. The results suggest that a preferred nucleation on the basis of the residual particles of Φ phase be the origin of anisotropy of HDDR-received powders, but a random nucleation under lower ps produces negative effect on the development of anisotropy.
Key words: NdFeB HDDR< microstructure anisotropy
