Effect of surface modification on microwave absorbing properties of magnetic metal fibers

Abstract

In order to avoid forming an electrical conductive network due to surface connections, the magnetic metal fibers were coated with SiO₂ for surface modification by the sol-gel process. The microstructure, composition and electromagnetic characteristics of SiO₂-coated and uncoated metal fibers were studied using SEM, EDAX, and a voter network analyzer. The reflectivity was simulated using the RAMCAD software. The electromagnetic parameters and absorption properties of SiO₂-coated metal fibers were improved greatly due to optimal impendence matching and the electric conductivity decreased, compared to those of uncoated materials.

Keywords

magnetic metal fiber / SiO₂ film / electromagnetic parameters / microwave absorption / surface modification

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