Study on the microwave absorbing properties of SiC@Ni powders with core@shell structure

Abstract

Hybridization of dielectric and magnetic materials is considered a promising option for the preparation of electromagnetic wave absorbing materials with excellent properties. In this paper, SiC@Ni powders were prepared by a surface heat-assisted process, in which SiC was first cleaned sequentially with anhydrous ethanol and NaOH solutions, and the samples were etched into a mixed solution of HF and HCl, the SiC@Ni powders were then mixed at high speed at 120 °C under argon atmosphere. The sample were characterized by Scanning electron microscopy (SEM) and vector network analyzer (VNA). It is found that the absorption characteristics of SiC@Ni in the 2–18 GHz band are significantly enhanced due to the introduction of the ni layer which enhances the loss of the sample to solve the problem of a single absorption mechanism and high impedance of SiC. The reflection loss value of SiC@Ni in the 8.7 GHz band decreases to − 22.45 dB when the material thickness is 2.5 mm, the effective absorption frequency width is 2.5 GHz, which is a significant advantage over the initial SiC. The experimental methodology of this work is simple and easy to follow, and provides some guidance for the large-scale production of SiC-based microwave absorbing materials.