# Effect of CeO2@GNPs on the Corrosion Properties of 2024 Alloy
###### Abstract  
The nanocomposites of 2024 Al reinforced with CeO2@GNPs (graphene) nanoparticles were fabricated using the hot-press sintering method. With the addition of 0.5 wt% CeO2@GNPs, the YS and UTS of the fabricated nanocomposites increased by 21.1% and 24.7%, respectively. The load transfer effect and optimization of the interfacial bonding were the main factors to improve the mechanical properties of the composites. The effect of the surface modification of GNPs on the corrosion resistance of the composites was investigated, demonstrating that the addition of GNPs weakened the corrosion resistance of the fabricated nanocomposites. Meanwhile, the corrosion current density (2.776 \(\times\) 10\({}^{-3}\) A\(\cdot\)cm\({}^{-2}\)) and polarization resistance (13.971.37 \(\Omega\) cm\({}^{2}\)) of the prepared composites with CeO2 nanoparticle-layered GNPs exhibited a significant decreasing trend compared with the composites without a CeO2 nanoparticle layer (3.540 \(\times\) 10\({}^{-3}\) A\(\cdot\)cm\({}^{-2}\), 10,199.72 \(\Omega\) cm\({}^{2}\)). Optimizing the dispersion of GNPs and their interfacial bonding with the aluminum matrix promoted the reduction in the corrosion area and the possibility of micro-couple formation, leading to an effective enhancement of the corrosion resistance of the nanocomposites.  
aluminum matrix composites (AMCs); graphene nano-platelets; polarization resistance; corrosion current density +
Footnote †: journal: Applied  
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0000-0002-2000-2000][PERSON]  
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compared to the addition of raw CNTs. [PERSON], [PERSON] et al. reported that the improvement in the mechanical properties of the composites was mainly attributed to the good adherence at the interface between the Ni-CNTs and Mg matrix and no structural damage of the CNTs due to the presence of Ni coating [11; 12]. These reports suggested that surface modification techniques are beneficial for improving the interfacial bonding of carbon nanomaterials with the matrix and enhancing the mechanical properties of the metal composites. In fact, most studies have mainly reported the structural and mechanical properties of AMCs reinforced with GNPs. However, one of the main reasons for the failure of the parts made of aluminum alloy is corrosion. The study of the corrosion properties of aluminum alloys is also crucial [13; 14] apart from the mechanical properties. In the field of the corrosion resistance of metallic materials, engineers or researchers prefer to enhance the corrosion resistance of materials by coating their surfaces due to its high efficiency [15]. Few studies have provided insight into the corrosion behavior of those composites through the addition of reinforcements.  
As we know, 2024 Al is widely used in aircraft skins, skeletons, truck hubs, propeller components and a variety of other structural components, where its mechanical properties and corrosion resistance play an important role in daily services. Therefore, it is necessary to study the corrosion behavior of aluminum matrix composites to ensure their reliability and safety during use. In the present study, the composites of 2024 Al reinforced with CeO\({}_{2}\)@GNPs nanoparticles were fabricated using the hot-press sintering method. The intention was to strengthen the mechanical properties of the 2024 aluminum alloy while ensuring the effectiveness of its corrosion resistance. The reinforcement GNPs, on the other hand, were used to enhance their bonding to the matrix using surface-coated techniques. The mechanical properties and corrosion behavior were investigated for those composites and the matrix. Meanwhile, comparative experiments for the electrochemical properties were designed to investigate the influence of CeO\({}_{2}\) cladding on the corrosion behavior of the composites.