Heteroatom Modification Enhances Corrosion Durability in High-Mechanical-Performance Graphene-Reinforced Aluminum Matrix Composites

The antagonism between strength and corrosion resistance in graphene-reinforced aluminum matrix composites is an inherent challenge to designing reliable structural components. Heteroatom microstructural modification is highly appreciated to conquer the obstacle. Here, a bottom-up strategy to exploit the heterogeneous phase interface to enable high corrosion durability is proposed. Deformation-driven metallurgy derived from severe plastic deformation is developed to produce Mg-alloyed fluorinated graphene structures with homogeneous dispersion. These structures allow for absorbing corrosion products, forming a dense protective layer against corrosion, and local micro-tuning of the suppression of charge transfer. This results in superior corrosion resistance with an outstanding strength-ductility balance of the composites via ultrafine-grained and precipitation strengthening. The anti-corrosion polarization resistance remains 89% of the initial state after 2-month immersion in chloride-containing environment, while the ultra-tensile strength and elongation of 532 +/- 39 MPa and 17.3 +/- 1.2% are obtained. The economical strategy of heteroatom modification broadens the horizon for anti-corrosion engineering in aluminum matrix composites, which is critical for the design of carbonaceous nanomaterial-reinforced composites to realize desired performances for practical applications.

Automated summary

In this study, a bottom-up strategy utilizing heteroatom microstructural modification is proposed to overcome the antagonism between strength and corrosion resistance in graphene-reinforced aluminum matrix composites. The deformation-driven metallurgy technique is used to produce Mg-alloyed fluorinated graphene structures, which can absorb corrosion products, form a dense protective layer, and suppress charge transfer. The results demonstrate excellent corrosion resistance and strength-ductility balance.