回火过程中NdFeB系永磁合金的组织结构与磁性能

Changes of Magnetic Properties and Microstructure of NdFeB Ternary System Alloys during Annealing Process

摘要: 本文研究了NdFeB三元系永磁合金在恒温(773~1023K)回火过程中组织结构与性能的变化。实验结果表明:在回火初期(1~3min)矫顽力较快地提高,达到峰值后矫顽力又降低。回火温度越低,矫顽力达到峰值所需的时间越长,与烧结态相比,回火后矫顽力可提高1倍。回火前后合金的基体相没有变化,都是单相的,没有缺陷。回火过程仅是晶界,特别是晶界交隅处发生晶化与共晶转变。回火后矫顽力的提高与晶界的变化有关。

Abstract: Under temperatures (773~1023K), the results show that in early stage of annealing the coercivity increases sharply and after a peak value, it decrease again. The coercivity for the specimens under annealing state was enhanced one time compared with that of the sintered state. The matrix phase was single phase, in which no crystalline defect was found and the matrix phase was unchanged, only the grain boundaries change. The increase of the coercivity ofter annealing was connected with the changes of grain boundaries.