Abstract：Graphene nanoflakes (GNFs) reinforced aluminum matrix composites were prepared by compressing-sintering-hot extrusion process, and their compressive properties were tested. The results show that GNFs/Al composites are high strain rate sensitive materials. When the strain rate increases from 10-3s-1 to 3×103s-1, the strength of the composites increases obviously. However, when the strain rate further increases to 5×103s-1, the strength of the composites declines a little due to the internal thermal softening of the material. Dynamic recrystallization occurs in the matrix of the composites after dynamic compression, and the higher the strain rate is, the more significant the dynamic recrystallization is. At the same time, the enhanced phase GNFs remain intact and bonded with matrix in atom scale while undergo a distorted deformation. Therefore, the plasticity of graphene reinforced aluminum matrix composites under dynamic compression is excellent.
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