Study on electromagnetic wave absorbing properties of nanocrystalline Fe81.5Si3B9P3C1Cu1Ti1.5/Graphene oxide composite

Abstract

To prevent and control electromagnetic pollution problems, there is an urgent need to develop better wave-absorbing materials. In this study, nanocrystalline alloy/graphene oxide(GO) composite modified powder was obtained on the basis of Fe81.5Si3B9P3C1Cu1Ti1.5 nanocrystalline alloy powder with different weight percentages of GO, which was mechanically mixed by high-energy ball milling treatment, and the microstructure and morphology of the materials and the electromagnetic wave absorption properties were characterized. The results show that the Fe81.5Si3B9P3C1Cu1Ti1.5/GO composite powder has excellent wave absorption performance, and the loss mechanism is magnetic loss including eddy current loss and natural resonance. Defects and groups in GO not only improve the impedance matching characteristics, but also introduce defect polarization relaxation and electron dipole polarization relaxation of the groups, which are beneficial to the penetration and absorption of electromagnetic waves. The minimum reflection loss (RLmin) of the nanocrystalline alloy powder can reach −37.55 dB and the maximum effective absorption bandwidth (ΔfRL<-10dB) can reach 5.95 GHz; the RLmin of the composite powder is as high as −52.55 dB when the GO content is 1.5 wt%, and the widest bandwidth can reach 6.12 GHz at 2.00 mm when the GO content is 0.5 wt%. With the addition of GO, its RLmin increased by 40%. This indicates that the composite material have superior absorption performance compared to a single absorber.