Corrosion Inhibition of Rare Earth Salt of Nd(NO₃)₃ to 1060 Aluminum in HCl Medium

The corrosion inhibition of rare earth salt of Nd(NO₃)₃ to 1060 aluminum in 1.0 mol/L HCl solution at 25 ℃ was studied by polarization curve method and electrochemical impedance spectroscopy (EIS) method. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to characterize the microstructure of the aluminum surface before and after corrosion. The results show that Nd(NO₃)₃ could efficiently retard the corrosion of aluminum in HCl solution. And the inhibition efficiency increased with the increase of Nd(NO₃)₃ content. The inhibition efficiency could hit 96.9% by polarization curve method and 88.6% by EIS method when the mass concentration of Nd(NO₃)₃ was 500 mg/L. Nd(NO₃)₃ mainly retarded cathodic reaction, so it was a cathodic inhibitor. Adding 500 mg/L Nd(NO₃)₃ could sharply reduce the corrosion degree of aluminum surface, showing good corrosion inhibition performance.