Two-step plasma electrolytic oxidation of Ti-15V-3Al-3Cr-3Sn for wear-resistant and adhesive coating

► Two-step PEO was carried out to form a wear-resistant coating on Ti-15V-3Al-3Cr-3Sn. ► The first step PEO in alkaline aluminate electrolyte formed a wear-resistant coating. ► The second step PEO in acid electrolyte improved the coating adhesion markedly. ► During the second step PEO, voids near the alloy/coating interface were healed.