PEO of additively manufactured Al10SiMg alloy: Effects of α-Al2O3 particles on energy consumption and wear behaviour

Abstract

Plasma electrolytic oxidation (PEO) coatings were developed on an additively manufactured Al10SiMg alloy pre-treated with hard anodizing (HA). The influence of α−Al2O3 particles incorporated during PEO was evaluated in terms of energy consumption, coating morphology, composition and wear behaviour. Combining a 20 μm-thick HA precursor and a PEO electrolyte with suspended α−Al2O3 particles resulted in the highest energy savings (∼60%). Wear volume loss measurements and wear track characterization revealed that the PEO coating with added particles (PEOP) outperformed the coating without particles and a conventional hard anodizing layer. This superiority was attributed to the partial sealing of the outer porous layer by the incorporated α−Al2O3 particles as well as the reduced SiO2 content and the formation of a W-rich tribolayer on the wear track surface.