Preparation of Graphite/Ferrite/Resin‐Based Composite High‐Efficiency Wave‐Absorbing Materials by Selective Laser Sintering

Abstract

The ideal absorbing material should be “wide, light, thin, and strong”. In this paper, Graphite/Fe3O4/resin‐based composite absorbers were prepared by selective laser sintering and vacuum impregnation of epoxy resin. The effects of different Graphite‐Fe3O4 powder compositions on the absorbing and mechanical properties of the composites were investigated. The results showed that with the increase of Fe3O4 content, the absorption performance of the composites firstly increased and then decreased, and the absorption peak gradually moved from high frequency (12‐18 GHz) to low frequency (2‐8 GHz). The bending strength of composites decreased with the increasing of Fe3O4 content, from 18 Mpa to 8 Mpa gradually, which was consistent with the change of open porosity. When the mass ratio of Graphite‐Fe3O4 was 4:3, the wave absorption performance was the best, the minimum RL was ‐54.8 dB, the effective absorption bandwidth was 2.8 GHz (8.72‐11.52 GHz), and the bending strength was 11 MPa, which was 9 times higher than that of SLS plain billets. This is because the increase of the Fe3O4 content in the hybrid powder increased the number of heterogeneous interfaces, but decreases the number of holes inside the composite, which affected the number of microwave reflections inside the material, resulting in different wave absorption and mechanical properties. The graphite/ferrite/resin matrix composites prepared by SLS technology achieved the synergy of lightweight, high strength, and good wave absorption properties, and have a broad industrial application prospect.This article is protected by copyright. All rights reserved.