用于永磁电机的理想的功能材料—Nd-Fe-B永磁体

Ideal Functional Material:NdFeB Permanent Magnet for Electric Machines

Nd-Fe-B永磁已广泛应用于各种电机之中,可使电机体积小、重量轻、比功率高。如果电机设计得好,不但不会增加成本,从总体效果来看,甚至会使成本降低。影响Nd-Fe-d永磁在电机中使用的主要障碍是_iHc的温度系数太大。大幅度提高磁体的iHC,可以使Nd-Fe-B的热稳定性得到明显改善。在200℃以内使用改善了热磁特性的Nd-Fe-B永磁并不比钐钴类磁体的热稳定性差。一般电机的使用温度在100～130℃左右,在此温度下磁体仍然具有一条接近线性的B-H曲线。预稳定处理可以消除磁体的不可逆损失。环氧树脂涂层是防止磁体锈蚀的最好办法。

NdFeB permanent magnet has been extensively used for various electric machines, making them smaller in size, lighter in weight and higher in efficiency. Thoughtful design of the electric machine may reduce the productional cost. The main problem in using NdFeB magnet for electric machines is its high temperature coefficint in jHc.However,remarkable improvement can be seen of its thermal stability when jHc is significantly raised. Thus, thermal stability of SmCo does not better than NdFeB blow 200℃.At the temperature 100～130℃ which the electric machines usually be operated, NdFeB can still give BH curves almost linear. Pre-stabilizing treatment may eliminate irreversible loss and epozy resin coating may serve as an effective anti-corrosive measure.