Microstructure and Microwave Absorbing Properties of Er-Fe-V Ternary System

摘要

The microstructure of the Er-Fe-V ternary system at 773 K was investigated by means of x-ray diffraction analysis and scanning electron microscopy. The isothermal section at 773 K was obtained, consisting of 9 single-phase regions, 15 two-phase regions, and 8 three-phase regions. The homogeneity range of the ternary compound ErFe12-xVx was determined to be x = 1.1 to 2.6. The maximum solid solubility of V in Fe, ErFe2, and Er2Fe17 was found to be about 13.0 at.%, 5.3 at.%, and 2.5 at.%, respectively. The maximum solid solubility of Fe in V was found to be about 25 at.%. Regarding the microwave absorbing properties of V-doped Er2Fe17 alloy, the absorption peak of the Er2Fe17-xVx alloys moved toward the low frequency region while the minimal reflection loss decreased upon V addition, with absorption frequency bandwidth (R -5 dB) of about 6.7 GHz. For coating thickness of 1.8 mm, the minimal reflection loss of Er2Fe17-xVx alloys with x = 0, 0.38, 0.76, and 1.14 was found to be -20.7 dB, -14.8 dB, -9.0 dB, and -7.0 dB at 8.9 GHz, 8.5 GHz, 6.8 GHz, and 6.0 GHz, respectively.