Preparation and Microwave-Absorbing Properties of FeCo Alloys by Condensation Reflux Method

Five groups of FeCo alloy samples with different atomic ratios of Fe/Co (3:7, 4:6, 5:5, 6:4, 7:3) were prepared using the condensation reflux method. The results indicate that varying the atomic ratios of Fe/Co has a significant impact on the microstructure, electromagnetic parameters, and microwave absorption properties of FeCo alloys. As the Fe atom content increases, the morphology of the FeCo alloys transitions from irregular flower-shaped to uniformly spherical and eventually to lamellar. The attenuation of electromagnetic waves in the five groups of alloys is primarily due to magnetic loss. Among them, Fe₆Co₄ exhibits the best absorption performance, with a minimum reflection loss (RL) value of -35.56 dB at a frequency of 10.40 GHz when the matching thickness is 7.90 mm. Additionally, at a matching thickness of 5.11 mm, the maximum effective absorption bandwidth (EAB) reached 2.56 GHz (15.44-18 GHz).