In present study, the microstructure, mechanical and electrochemical properties of aluminum-graphene nanoplatelets (GNPs) composites were investigated before and after extrusion. The contents of graphene nanoplatelets (GNPs) were varied from 0.25 to 1.0. wt.% in aluminum matrix. The composites were fabricated thorough powder metallurgy method, and the experimental results revealed that Al-0.25%GNPs composite showed better mechanical properties compared with pure Al, Al-0.50%GNPs and Al-0.1.0%GNPs composites. Before extrusion, the Al-0.25%GNPs composite showed ~13.5% improvement in ultimate tensile strength (UTS) and ~50% enhancement in failure strain over monolithic matrix. On the other hand, Al-0.50%GNPs and Al-0.1.0%GNPs composites showed the tensile strength lower than monolithic matrix. No significant change was observed in 0.2% yield strength (YS) of the composites. However, the extruded materials showed different trends. The 0.2%YS of composites increased with increase in GNPs filler weight fractions. Surprisingly, UTS of composites with 0.25 and 0.50% GNPs was lower than monolithic matrix. The failure strain of the baseline matrix was enhanced by ~46% with 0.25% graphene nanoplatelets. The superior mechanical properties (in terms of failure strain) of the Al-0.25%GNPs composite maybe attributed to 2-D structure, high surface area and curled nature of graphene. In addition, the corrosion resistance of pure Al and its composites reinforced with 0.5 and 1.0. wt% GNPs was also investigated. It was found that the corrosion rate increased considerably by the presence of GNPs.
Rashad, M., Pan, F., Yu, Z., Asif, M., Lin, H., & Pan, R. (2015). Investigation on microstructural, mechanical and electrochemical properties of aluminum composites reinforced with graphene nanoplatelets. Progress in Natural Science: Materials International, 25(5), 460–470. https://doi.org/10.1016/j.pnsc.2015.09.005