The mechanical, corrosion and tribological properties of Al2O3 films grown by anodisation and MAO

Al-5083 alloys are used as a marine part due to resistance to harsh environment. However, mechanical and corrosion resistance to seawater is not sufficient. For this purpose, many different surface treatments, electrochemical coatings, etc. are used to increase the mechanical, wear and corrosion resistance of the surface of Al-5083. This works aims to enhance mechanical, corrosion and tribological properties of Al-5083. Therefore, in this study, the oxide surface was enlarged on the Al-5083 alloy by anodisation and MAO techniques. Three different current densities (25 mA/cm(2), 50 mA/cm(2) and 75 mA/cm(2)) were used in the anodisation process. In the MAO process, three different voltages (400 V, 420 V and 440 V) were used. SEM, XPS and AFM were used for microstructure after anodisation and MAO processes. Scratch and hardness test were used to determine mechanical properties, and pin-on-disc was used to determine tribological properties. Also, electrochemical test was used to evaluate the corrosion properties. According to studies compared, it has been observed that the anodisation technique in Al-5083 alloy is better than the MAO technique. Corrosion and mechanical strengths decreased with increasing voltage and current density in both techniques.