Effect of Aluminum on the Corrosion Resistance of Nickel Aluminum Bronze Alloy in Saline Water

The corrosion resistance of nickel-aluminum bronze alloy in 3.5% (mass fraction) NaCl solution was investigated by electrochemical methods, and the morphology and elemental composition of corrosion products were analyzed by scanning electron microscopy and energy spectrum. The results showed that the corrosion resistance of the nickel-aluminum bronze alloy increased with the increase of immersion time, and a protective film of aluminum oxide and cuprous oxide was formed on the surface of the alloy to protect the inner metal substrate. When the mass fraction of aluminum was 9%, the alloy had the best corrosion resistance, and a dense and uniform protective layer was formed on the surface of this material, which effectively slowed the medium corrosion to the alloy.