Morphological, electromagnetic and absorbing properties of GR/Fe93.5Si3.5La1Ce2 composite powders

Abstract

In this study, the morphological, electromagnetic and absorbing properties of GR/Fe93.5Si3.5La1Ce2 composite powders were systematically investigated. The composite powders was prepared by high-energy ball milling. X-ray diffractometer (XRD) and Raman spectroscopy analyses confirm the presence of α-Fe and graphene in the composite powders. Scanning electron microscopy (SEM) observation shows that the composite powders have a flake morphology. The electromagnetic and absorbing properties of the composite powders were analyzed with a vector network analyzer. When the milling time and graphene content are 12 h and 1 wt%, respectively, the composite powders exhibit the best absorbing property. For 1.0 wt% GR/Fe93.5Si3.5La1Ce2 composite at 0.3 GHz, the ε′ and ε" are 77.76 and 124.73, and the μ′ and μ" are 6.09 and 2.83. Its tanδε, tanδμ and tanδ reach 0.63, 13.80 and 14.43, respectively, which basically increased the tanδ by more than 2 times compared with other composite powders. This indicates that the composite powder has excellent wave absorption performance. Meanwhile, the analysis shows that the loss mechanism of the composite powder is mainly relaxation loss, conduction loss, eddy current loss and natural resonance. Therefore, this composite powder provides a new approach for the development of wave absorbing materials.