烧结Nd-Fe-B磁体的磁性能一致性与其微观结构的关系

分析了微观结构和热处理工艺对矫顽力的影响,发现在矫顽力一定的情况下,磁体的微观结构越“差”,则保证不同批次磁体矫顽力变化不大于某一给定值所需的工艺条件就越严格;反之则越宽松.就同一炉产品而言,微观结构越好的磁体,其矫顽力受烧结(热处理)炉温度梯度的影响越小,其结果是该炉产品的一致性越高.反之,受温度梯度的影响越大,磁体的一致性也就越低.该研究结果说明:在条件许可的情况下,应首先考虑通过改善磁体的微观结构来提高磁性能一致性. 关键词： Nd-Fe-B永磁体 微观结构 内禀矫顽力 一致性

INVESTIGATION OF THE RELATIONSHIP BETWEEN THE CONSISTENCE AND MICROSTRUCTURE OF SINTERED Nd-Fe-B MAGNETS

One of the most important factors that lower the consistence is the appearance of regions where the technological parameters deviate from the points where the sensors are located. In this paper this was investigated on the basis of the relationship between the intrinsic coercivity and the microstructure parameters of sintered Nd-Fe-B magnets. It is found that the magnet with a fairly good microstructure will have higher consistence than the magnet with a relatively poor microstructure under the same technological conditions. This indicates that the more effective approach to enhance the consistence of a magnet is to optimize its microstructure other than to rigorously enforce the technological conditions. The results obtained show some directive for improving the consistence of the magnetic properties of sintered Nd-Fe-B magnets.