▎ 摘　　要

Graphene is a significant reinforcement in metal matrix composites by virtue of its superior mechanical properties. The cracking of metal crystal and the failure of graphene-metal interface are the main reasons for the decrease of mechanical properties of graphene/metal composites, but the damage mechanism of that is not clear. In this paper, a novel two-dimensional microstructure model of graphene/polycrystalline metal composites is established by a self-developed structure modeling procedure. According to the actual structure of graphene/metal composites, the numbers, sizes, orientations, arrangements of graphene and grain can be controlled respectively. Moreover, by employing the method of combining the crystal plasticity finite element method (CPFEM) and the cohesive zone model (CZM), the damage mechanism of graphene/aluminum (Al) composites on polycrystalline Al matrix, graphene-reinforcement and graphene-Al interface under tensile load is revealed from the mesoscale for the first time, then the effects of graphene morphology and initial microcracks on the failure behavior and overall mechanical properties of graphene/Al composites are fully captured. This study provides a strong theoretical support and inspiration for the construction of graphene/Al composites with excellent properties.