Effect of ball milling time on graphene nanosheets reinforced Al6063 composite fabricated by pressure infiltration method

摘要

Evolution of graphene nanosheets (GNSs) during mechanical milling process was investigated to fabricate GNSs/Al nanocomposite by routes combined of pressure infiltration and hot extrusion. The structural integrity and dispersion homogeneity of GNSs together with the degree of interfacial reaction were systematically discussed. It was revealed that a moderate milling time existed for well dispersion and small quantities of Al4C3 (partial reaction bonding) via mechanical milling technique. A highest tensile strength of 276 MPa was obtained only with 0.3 wt% GNSs, which was 22.5% enhancement over the unreinforced Al matrix with the same preparation process and no decrease in elongation. Meanwhile, compared with reference Al, a great enhancement of electrical conductivity was achieved about 17.4%, which had not been reported previously. This study could provide new insights into the control factors of mechanical milling process for GNSs/Al composite and improve the interfacial bonding condition in situ during ball milling and subsequent densification processes to take full advantage of the extraordinary performance of graphene in metal matrix composites. (C) 2018 Elsevier Ltd. All rights reserved.