▎ 摘　　要

Three-dimensional (3D) graphene/SiBCN composites (GF/SiBCN) were prepared by depositing SiBCN ceramics in 3D graphene foam via the chemical vapor infiltration technique. The effect of the heat treatment temperature on the microstructure, phase composition, and electromagnetic properties of the GF/SiBCN composite was investigated. The SiBCN ceramics maintained an amorphous structure in the composite below 1400 degrees C above which the crystallinity of the free carbon phase gradually increased. While the Si3N4 and B4C phases started to crystallize at 1500 degrees C and their crystallinity increased with temperature, SiC was observed at 1700 degrees C. The electromagnetic shielding effectiveness of GF/SiBCN increased with the heat treatment temperature. (C) 2019 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.