Abstract
In order to obtain better corrosion resistance, the micro-arc oxidation (MAO) coating after adding (Y(NO3)3⋅63⋅6H2O was sealed by TiO2 sol–gel method. Dynamic polarization curves and electrochemical impedance spectroscopy show that the prepared samples (Y(NO3)3⋅63⋅6H2O content was 1.5g/L) have good corrosion resistance (1.2308×10−91.2308×10−9A⋅cm−2⋅cm−2) in 3.5wt.% NaCl aqueous solution. Afterward, the samples with a concentration of 1.5 g/L of Y(NO3)3⋅63⋅6H2O were sealed by TiO2 sol–gel. Through SEM, XRD and electrochemical test, it is found that the surface of the film is smooth, the phase is mainly in the form of Anatase-TiO2 and has better corrosion resistance (7.593×10−97.593×10−9A⋅cm−2⋅cm−2). This showed that sealing the doped 2024 aluminum alloy MAO film can significantly reduce the corrosion sensitivity and corrosion rate of the film.
