Development of Al-and Cu-based nanocomposites reinforced by graphene nanoplatelets: Fabrication and characterization

摘要

Aluminum and copper matrix nanocomposites reinforced by graphene nanoplatelets (GNPs) were successfully fabricated by a wet mixing method followed by conventional powder metallurgy.The uniform dispersion of GNPs within the metal matrices showed that the wet mixing method has a great potential to be used as a mixing technique.However,by increasing the GNPs content,GNPs agglomeration was more visible.DSC and XRD of Al/GNPs nanocomposites showed that no new phase formed below the melting point of Al.Microstructural observations in both nanocomposites reveal the evident grain refinement effect as a consequence of GNPs addition.The interracial bonding evaluation shows a poor interracial bonding between GNPs and Al,while the interfacial bonding between Cu and GNPs is strong enough to improve the properties of the Cu/GNPs nanocomposites.In both composites,the coefficient of thermal expansion decreases as a function of GNPs while,their hardness is improved by increasing the GNPs content as well as their elastic modulus.