Effects of K[sub.2]TiF[sub.6] and Electrolyte Temperatures on Energy Consumption and Properties of MAO Coatings on 6063 Aluminum Alloy

To decrease energy consumption and improve the performance of micro-arc oxidation (MAO) films on 6063 Al alloy, a policy of K[sub.2]TiF[sub.6] additive and electrolyte temperature control was adapted. The specific energy consumption relied on the K[sub.2]TiF[sub.6] additive and more particularly on the electrolyte temperatures. Scanning electron microscopy demonstrates that electrolytes with 5 g/L K[sub.2]TiF[sub.6] can effectively seal the surface pores and increase the thickness of the compact inner layer. Spectral analysis shows that the surface oxide coating consists of γ-Al[sub.2]O[sub.3] phase. Following 336 h of the total immersion process, the impedance modulus of the oxidation film, prepared at 25 °C (Ti5-25), remained 1.08 × 10[sup.6] Ω·cm[sup.2]. Moreover, Ti5-25 has the best performance/energy-consumption ratio with a compact inner layer (2.5 ± 0.3 μm). This research found that the time of the big arc stage increased with the temperature, resulting in producing more internal defects in the film. In this work, we employ a dual-track strategy of additive and temperature providing an avenue to reduce the energy consumption of MAO on alloys.