Microstructure and corrosion evaluations for Al2O3 –leaded brass matrix nanocomposites in marine solution

Hancing the corrosion resistance of various composites is a challenge; however, the mechanical characteristics of composites are usually high without any risks. Thus, in this paper, Al2O3 nanoparticles with various percentages as reinforcements were added to the brass matrix to increase the corrosion resistance. Tafel polarization, electrochemical impedance spectroscopy (EIS), and weight loss measurements were performed to investigate the corrosion characteristics of manufactured nanocomposites. Moreover, field emission scanning electron microscopy (FESEM) was used to study the surface morphology of nanocomposites before and after exposure of specimens to 0.6 M NaCl solution. FESEM images and the related energy dispersive spectroscopy results showed that Al2O3 nanoparticles were distributed in the α-phase of the matrix homogeneously. Corrosion rates of nanocomposite decreased significantly by about 41–99% compared to the matrix without reinforcement. Weight loss measurements showed that the weight loss of nanocomposites at 95 °C was lower than that at 25 °C. This was attributed to the formation of copper/zinc chloride salts on corroded surfaces. •New corrosion-resistant leaded-brass matrix nanocomposite made by casting.•The optimum percentage of Al2O3 nanoparticles in the matrix was 1.5 wt%.•The utilized nanoparticle reduced the corrosion rates by about 100%.•Al2O3 nanoparticles were distributed homogeneously in the matrix.