Aluminium dan paduannya banyak digunakan dalam industri konstruksi, otomotif, manufaktur, dan kedirgantaraan karena sifatnya ringan dan kuat. Namun, lapisan oksida alami aluminium memiliki keterbatasan dalam lingkungan korosif, sehingga diperlukan peningkatan sifat permukaan. Plasma Electrolytic Oxidation (PEO) merupakan metode yang efektif untuk membentuk lapisan oksida pelindung dan meningkatkan ketahanan korosi. Untuk meningkatkan performa lapisan hasil PEO, dilakukan penyisipan material berbasis nanokarbon seperti reduced graphene oxide (rGO) yang meningkatkan kepadatan lapisan oksida. Dalam penelitian ini, (rGO) disisipkan ke dalam lapisan PEO pada paduan aluminium AA7075-T735. Proses PEO dilakukan menggunakan elektrolit 30 g/L Na₂SiO₃, 30 g/L KOH, dan 10 vol% etanol dengan konsentrasi rGO 0,2 g/L dan 2 g/L. Pengujian korosi dilakukan melalui uji elektrokimia EIS dan PDP. Sifat mekanik lapisan diuji dengan uji kekerasan dan ketahanan aus. Hasil penelitian menunjukkan bahwa penambahan rGO sebesar 0,2 g/L memberikan ketahanan korosi terbaik, dengan penurunan rapat arus korosi hingga 1,41 × 10⁻⁷ A/cm² dan resistansi polarisasi sebesar 9,42 × 10⁷ Ω·cm² dibanding lapisan tanpa rGO dengan rapat arus korosi 2,21 x 10-6 A ∙ cm-2 dan resistansi polarisasi 3,57 × 107 Ω·cm². Sementara itu, penambahan rGO sebesar 2 g/L meningkatkan kekerasan lapisan dari 151,09 HVmenjadi 175,66 HV dan memperbaiki ketahanan aus dari 2,08 x 10-6 mm3/mm menjadi 0,68 x 10-6 mm3/mm. Hasil ini menunjukkan bahwa rGO berperan dalam meningkatkan ketahanan korosi dan mekanik lapisan PEO.

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Aluminum and its alloys are widely utilized in the construction, automotive, manufacturing, and aerospace industries due to their lightweight nature and high strength. However, the natural oxide layer formed on aluminum exhibits limited protection in corrosive environments, thereby necessitating surface modification. Plasma Electrolytic Oxidation (PEO) is an effective technique for producing protective oxide layers and improving corrosion resistance. To enhance the performance of PEO coatings, nanocarbon-based materials such as reduced graphene oxide (rGO) were incorporated to increase oxide layer compactness. In this study, rGO was introduced into the PEO coating on AA7075-T735 aluminum alloy. The PEO process was carried out using an electrolyte containing 30 g/L Na₂SiO₃, 30 g/L KOH, and 10 vol% ethanol, with rGO concentrations of 0.2 g/L and 2 g/L. Corrosion behavior was evaluated through EIS and PDP, while mechanical properties were assessed via hardness and wear resistance tests. The results showed that the addition of 0.2 g/L rGO provided the best corrosion resistance, lowering the corrosion current density to 1.41 × 10⁻⁷ A/cm² and increasing polarization resistance to 9.42 × 10⁷ Ω·cm², compared to the coating without rGO, which showed a corrosion current density of 2.21 × 10⁻⁶ A/cm² and polarization resistance of 3.57 × 10⁷ Ω·cm². Meanwhile, the addition of 2 g/L rGO increased the coating hardness from 151.09 HV to 175.66 HV and improved the wear resistance from 2.08 × 10⁻⁶ mm³/mm to 0.68 × 10⁻⁶ mm³/mm. These results indicate that rGO plays a significant role in enhancing both the corrosion resistance and mechanical properties of the PEO coating.