Electromagnetic wave absorption properties of FeCoNiCrAl_(0.8) high entropy alloy powders and its amorphous structure prepared by high-energy ball milling

摘要

We investigated FeCoNiCrAl_(0.8) high entropy alloy and amorphous alloy powders synthesized simply via high energy ball milling for 10 and 20 h. The electromagnetic wave absorption properties of FeCoNiCrAl_(0.8) high entropy alloy and amorphous alloy powders were investigated. The structure and morphology of FeCoNiCrAl_(0.8) were analyzed by scanning electron microscopy with energy-dispersive spectrometry and x-ray diffraction, which demonstrated that FeCoNiCrAl_(0.8) powders were in irregular shape and monodisperse with an average size of 5-15 μm. The minimum reflection loss of FeCoNiCrAl_(0.8) high entropy alloy powders was -41.8 dB at 11.9 GHz with a thickness of 2.3 mm and effective bandwidth (RL ≤ -10 dB) was up to 4.7 GHz (8.7-13.4 GHz), while the minimum reflection loss of FeCoNiCrAl_(0.8) amorphous alloy powders was observed to be -35.5 dB at 14.6 GHz with a thickness of 1.7 mm and effective bandwidth varied from 12.7 to 16.3 GHz (3.6 GHz). Electromagnetic wave absorption properties of FeCoNiCrAl_(0.8) high entropy alloy powders is better than that of amorphous alloy powders, which demonstrated that phase structures of FeCoNiCrAl_(0.8) alloy powders affect electromagnetic wave absorption properties.