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 × 10−3 A·cm−2) and polarization resistance (13,971.37 Ω cm2) 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 × 10−3 A·cm−2, 10,199.72 Ω cm2). 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.

Keywords

• aluminum matrix composites (AMCs)
• graphene nano-platelets
• polarization resistance
• corrosion current density