Strengthening and toughening mechanisms in graphene-Al nanolaminated composite micro-pillars

Grain boundary-assisted deformation in graphene–Al nanolaminated composite micro-pillars

“…As demonstrated in Feng et al [15], when combined with site-specific microstructural analysis, micro-/nano-scaled mechanical characterization on small volume materials is a powerful tool in probing their deformation mechanism, owing to its capability in capturing the deformation characteristics across the entire gauge length [15], and its flexibility in studying the mechanical behaviour of materials with various crystallographic orientations [16]. Nevertheless, caution has to be exercised when one attempts to interpret bulk materials properties using the micro-/nano-mechanical data, as both mechanical strength and flow behaviour may show notable size effect when the dimension of the material is reduced to small scales [17][18][19].…”

“…Using a modified powder metallurgy fabrication technique, our research group developed bulk graphene (in the form of reduced graphene oxide, RGO)-Al composites with a bioinspired nanolaminated structure, and macroscopic tensile test revealed that these composites are both stronger and tougher than the pure Al matrix fabricated by the same approach [13,14]. Feng et al [15] further extended this study by carrying out uniaxial compression tests on micro-pillars fabricated from the bulk RGO-Al composites with different RGO concentrations and laminate orientations. It was found that the strengthening effect and efficiency of RGO can be enhanced by either orienting the RGO layers parallel with the loading direction or raising the RGO concentration, and the robust RGO/Al interfaces provide a crack deflection mechanism that toughens the composites.…”

Indentation-induced plastic behaviour of nanotwinned Cu/high entropy alloy FeCoCrNi nanolaminate: an atomic simulation

“…12 The strengthening capability in a micro-pillar of graphene/Al nanolaminated composites under uniaxial compression can be enhanced by either orienting the layers parallel with the loading direction or raising the concentration. 13 Subsequently, the remarkable strain hardening and high strength of the bulk graphene/Cu nanolaminated composites are reported, due to that the dislocation storage ability can be considerably improved through the novel grain-boundary engineering approach. 14 The tensile behavior of amorphous/amorphous nanolaminates shows the strength of the nanolaminates increases with the layer thickness decreasing, due to the interface obstruction to the shear band motion.…”

Composite structural modeling and tensile mechanical behavior of graphene reinforced metal matrix composites

“…The interfacial damage behavior can be expressed and determined by the damage factor D = ((σ n /σ 0 ) 2 +(σ s /σ 0 ) 2 ) 1/2 . For the graphene-Al interface, the interfacial strength σ 0 is determined as 140 MPa, the fracture energy Γ f is equal to 2 J m -2 , respectively [32,33]. In order to simulate the fracture mechanical behavior of Al matrix and graphene/ Al composites, the ductile damage criterion (in which the fracture strain ε f and displacement at fracture u f are usually applied) is applied for both graphene reinforcement and Al matrix, respectively.…”