▎ 摘　　要

Aluminum matrix composites strengthened with graphene sheets (Al-Gr) were fabricated by the combination of powder metallurgy and rolling methods. The morphologies and structures of Al-Gr powders as ball-milled were studied for different time. The effects of the graphene sheets content on the microstructures, density and wear property of the composites were also investigated. It is indicated that the graphene sheets are gradually dispersed into the aluminum matrix with increasing the ball-milling time and a uniform dispersion is achieved after ball-milling for 24 h. And no obvious agglomeration of graphene is observed in as-sintered and as-rolled composites for the contents of graphene sheets up to 1.0 wt.%. The coordinated deformation of multilayer graphene sheets occurs with the deformation of the surface grains during rolling, which may cause a significant reduction in the number of layers of graphene sheets. With increasing the graphene sheets contents, the density of the Al-Gr composites shows an decrease. The maximal hardness of Al-Gr composites were 89.3 +/- 3.2 HV at 0.7 wt.% of graphene content, showing 39.5% increments over pure aluminum. The coefficient of friction and wear rate in Al-Gr composites are significantly reduced compared with those in the matrix.