Improved mechanical property of nanolaminated graphene (reduced graphene oxide)/Al-Mg-Si composite rendered by facilitated ageing process

Bulk nanolaminated 0.4 wt% graphene (reduced graphene oxide, RGO)-reinforced Al-Mg-Si composite was fabricated using a modified powder metallurgy approach. The peakaged RGO-Al composite had significantly higher uniaxial yield (236.2. 10.8 MPa) and tensile strengths (320.3 +/- 4.0 MPa), but shared similar uniform elongation (9.8 +/- 0.5%) as compared to their unreinforced counterpart. These values are comparable or superior to the same series of alloys subject to complex thermo-mechanical treatments. Combining the mechanical test data with site-specific microstructural analysis, we rationalized the strength-ductility synergy in the composite by the refinement of the precipitates and the facilitated precipitation kinetics as a result of RGO incorporation, and the enhanced dislocation storage in the composite.