Abstract:The popularity of mobile communication and electronic devices has promoted social progress. However, the resulting electromagnetic pollution problems seriously reduce the quality of information transmission, and harm the health of organisms. Magnetic/dielectric composites exhibit excellent electromagnetic wave absorption properties due to good electromagnetic loss and impedance matching, which has become the focus of research. In this paper, three kinds of magnetic nanoalloy/graphene composites are prepared by the carbothermal reduction method. The results indicate that with the increase of sintering temperature, the increased defect density of graphene results in a decrease in permittivity, and the FeCoNi alloy exhibits high permeability attributed to its high saturation magnetization, which together optimizes the impedance matching of the composite. Therefore, FeCoNi/graphene composite absorbing material with a minimum reflection loss value of -63.8dB and an effective absorption bandwidth of 4.24GHz has been obtained. Moreover, the radar cross section results show that FeCoNi/graphene composite has good electromagnetic attenuation ability in simulated real environments, thus such the absorbing material is expected to be applied in complex electromagnetic environments.