Enhancing strength-ductility synergy of graphene/Al–Cu–Mg composites via forming MgAl2O4@graphene complex structure

The strength and ductility of graphene nanoplate (GNP) reinforced 2009Al composite (GNP/2009Al) were enhanced simultaneously, through wrapping MgAl2O4 around GNP and forming an MgAl2O4@GNP complex structure via in-situ reaction of CuO, Al and Mg during fabrication. This architecture generated numerous Al–MgAl2O4-GNP complex interfaces due to crystallographic orientation relationship of the Al–MgAl2O4 interface and the strong Al–O–C chemical bond, therefore, it not only enhances the load transfer efficiency of GNP but also improves the dislocation storage capacity of the Al matrix. These factors contributed to a stable and persistent working hardening capability for the GNP/2009Al composite. The feasible design proposed in this work, namely the in-situ Al–MgAl2O4-GNP complex strategy, can achieve improved tensile properties in GNP/2009Al composites. [Display omitted] •Via architecting nano-MgAl2O4 wrapping up GNP structure, the strength and ductility of MgAl2O4@GNP/2009Al composite enhanced simultaneously.•The strong interfacial bonding of MgAl2O4@GNP and Al can provide an adequate load transfer due to the chemical bonding between MgAl2O4 and GNP.•The presence of intragranular MgAl2O4 nanoparticles in the composite contributes to enhanced work hardening ability.