铁硼加入量对NdFeB材料吸波性能的影响

采用高能球磨和微氧化热处理方法制备了铁和硼含量不同的钕铁硼(NdFeB)吸波粉体,研究了铁硼加入量对NdFeB粉体吸波性能的影响。结果表明:所制NdFeB粉体和NdFe粉体均由α-Fe、Nd2O3和Fe2O3相组成;向Nd2Fe14B粉体添加30%的Fe后,其反射率最小值从–7.02 dB降低到–13.63 dB,吸收峰频率从6.80 GHz升高到10.6 GHz;NdFe粉体对电磁波的损耗以介电损耗为主,而NdFeB粉体对电磁波的损耗以磁损耗为主。向70%Nd2Fe14+30%Fe粉体加入B后,其反射率最小值降至–13.63 dB、吸收峰频率升至10.6 GHz。

Effects of Fe and B contents on the microwave absorbing properties of NdFeB

NdFeB powders with different contents of Fe and B were prepared through high energy ball milling and heat treatment in a low-oxygen atmosphere.The effects of Fe and B contents on the microwave absorbing properties of NdFeB powders were studied.The results indicate that all the prepared NdFeB and NdFe powders are composed of α-Fe、Nd2O3 and Fe2O3 phases.With the addition of 30%(mass fraction) Fe,the smallest value of reflectivity of Nd2Fe14B powder decreases from –7.02 dB to –13.63 dB,while the position of absorbing peak shifts from 6.80 GHz to 10.6 GHz.The main electroαmagnetic loss of NdFe powder is dielectric loss while the main electromagnetic loss of NdFeB powders is magnetic loss.Compared with the 70%Nd2Fe14+30%Fe powder,the smallest value of reflectivity of 70%Nd2Fe14B+30%Fe powder decreases to –13.63 dB,while the position of absorbing peak shifts to a higher frequency of 10.6 GHz.