Effects of anodization parameters on the corrosion resistance of 6061 Al alloy using the Taguchi method

Anodizing 6061 aluminum alloy (AA6061) in a H₂SO₄ electrolyte solution is a crucial process in the formation of anodic aluminum oxide (AAO) film for enhancing the material’s corrosion resistance. In this work, the effects of electrolyte concentration, current density, and anodization time parameters on the evolution of corrosion resistance in AA6061 alloy were investigated using the Taguchi method. Each anodization parameter had three levels using an experimental set of L9 orthogonal arrays. Variation in the bias voltage was recorded during the AAO process, and an energy-dispersive spectrometer was used to analyze the variations in the composition of the oxidized films. Variations in surface morphology and cross-sections of the AAO were examined using a scanning electron microscope. Finally, the potentiostatic polarization method was used to judge the relative corrosion resistance of the oxidized films. The oxidized film with the best corrosion resistance (I_corr = 8.516 × 10⁻¹¹ A/cm²) was obtained by anodizing at a current density of 1 A/dm² in 1 M sulfuric acid for 20 min.