中文摘要：

采用高能球磨及热处理方法制备Nd11.76Fe82.36B5.88和Nd11.76Fe77.36Cr5B5.88粉体,借助X射线衍射仪和矢量网络分析研究磁场热处理对粉体组织结构和微波吸收特性的影响。结果发现：在热处理过程中,加入磁场可以促进Nd11.76Fe82.36B5.88粉体各铁磁性相和非铁磁性相的晶粒长大,使Nd11.76Fe82.36B5.88粉体反射率的最小值从普通热处理粉体的-14 dB降低到-24.3 dB,Nd11.76Fe77.36Cr5B5.88粉体的反射率最小值从普通热处理粉体的-30.5 dB降低到-48 dB;磁场热处理使Nd11.76Fe82.36B5.88和Nd11.76Fe77.36Cr5B5.88粉体的吸波带变窄,且在微波损耗过程中,磁损耗作用增大,而介电损耗作用减弱。

英文摘要：

The Nd11.76Fe82.36B5.88 and Nd11.76Fe77.36Cr5B5.88 powders were prepared by the high-energy ball milling and following heat treatment.By the aid of X-ray diffraction and vector network analysis,the effects of the magnetic heat treatment on the powder structure and microwave absorbing properties were researched.The results show that applying magnetic field in the heat treatment process can promote the growth of ferromagnetic phase and non-ferromagnetic phase grain in Nd11.76Fe82.36B5.88 powder,the minimum reflectivity of Nd11.76Fe82.36B5.88 powder drops from the ordinary heat-treated -14 dB to -24.3 dB.The minimum reflectivity of Nd11.76Fe77.36Cr5B5.88 powder drops from the ordinary heat-treated -30.5 dB to -48 dB.The magnetic heat treatment of Nd11.76Fe82.36B5.88 and Nd11.76Fe77.36Cr5B5.88 powder will narrow the microwave absorbing bandwidth,and in the microwave loss process,the magnetic loss will increase,while the dielectric loss will decrease.