A Comprehensive Evaluation of Electrochemical Performance of Aluminum Hybrid Nanocomposites Reinforced with Alumina (Al₂O₃) and Graphene Oxide (GO)

Abstract

The electrochemical performance of in-house developed, spark plasma-sintered, Aluminum metal–matrix composites (MMCs) was evaluated using different electrochemical techniques. X-ray diffraction (XRD) and Raman spectra were used to characterize the nanocomposites along with FE-SEM and EDS for morphological, structural, and elemental analysis, respectively. The highest charge transfer resistance (Rct), lowest corrosion current density, lowest electrochemical potential noise (EPN), and electrochemical current noise (ECN) were observed for GO-reinforced Al-MMC. The addition of honeycomb-like structure in the Al matrix assisted in blocking the diffusion of Cl− or SO4−2. However, poor wettability in between Al matrix and Al2O3 reinforcement resulted in the formation of porous interface regions, leading to a degradation in the corrosion resistance of the composite. Post-corrosion surface analysis by optical profilometer indicated that, unlike its counterparts, the lowest surface roughness (Ra) was provided by GO-reinforced MMC.

Keywords

• aluminum metal–matrix composites
• hybrid nanocomposites
• graphene oxide (GO)
• Spark Plasma Sintering (SPS)
• electrochemical corrosion