Effect of TiO₂-PTFE on Micro-Arc Oxidation Coating of 6063 Aluminum Alloy

Abstract

In order to study the effect of TiO2 and PTFE on micro-arc oxidation coating of 6063 aluminum alloy, TiO2 and PTFE solid nanoparticles were added to the Na2SiO3 base electrolyte. The composite micro-arc oxidation coating was prepared on 6063 aluminum alloy by micro-arc oxidation (MAO) technology. The morphology, phase composition, element distribution, wear resistance and corrosion resistance of micro-arc oxidation ceramic coatings were studied by scanning electron microscope (SEM), X-ray diffraction (XRD), friction and wear tester and electrochemical workstation. Results indicated that the surface pore size of the composite coating prepared by adding 4 g/L TiO2 and 10 mg/L PTFE as composite additives was significantly reduced, thickness of the coating increased and the structure became dense. The friction coefficient decreased from 0.9 to 0.5, resulting in the best wear resistance. The electrochemical test showed that the self-corrosion potential of the composite coating was the highest (-0.18 V), and the self-corrosion current density was minimum (1.09 × 10-8 A/cm2).

Keywords

• aluminum alloy|micro-arc oxidation|tio₂|ptfe|wear resistance|corrosion resistance