改善金属基稀土永磁材料在交变场中抗涡损能力的研究

Analysis of eddy current effect on metallic rare earth permanentmagnetic materials under alternative magnetic field

金属基稀土永磁材料具有良好导电特性，在高频交变场环境下由于涡流效应损耗会降低其磁性能，尤其是难以应用在高转数电机领域。本文通过理论建模计算解释了涡流效应在磁体内变化的原因，从微观和宏观两方面，首次揭示了稀土永磁合金成分的显微分布形态对其自身绝缘特性的影响作用，以及解释了不同频率条件下材料电阻率存在差异的原因。并通过具体实验，制备得到具有优良绝缘特性、高性能稀土永磁体。

Rare earth permanent magnetic materials are a kind of electrical conductor, and its magnetic properties happen to fall because of eddy current, so that it＇s difficult to keep working stably for enough long time in high frequency AC field. In the present work, the reason of eddy current occurring in magnets was analyzed by setting up mathematical model. As far as rare earth permanent magnets concerned, for the first time, the relationship between microstructure and electrical insulation was reviewed. In additional, difference of respective resistance values also were explained clearly in different frequent. The rare-earth permanent magnets with stronger electrical insulation and high magnetic performance were obtained via establishing practical experiment.