Enhanced corrosion and tribocorrosion properties of duplex TiN-MAO coating prepared on TC17 alloys

The duplex TiN-MAO coating was fabricated on TC17 alloy by a hybrid treatment combining of micro-arc oxidation (MAO) and high power impulse magnetron sputtering (HiPIMS). A comprehensive analysis was carried out to study the corrosion and tribocorrosion performances of the bare and coated substrates. The electrochemical evaluation demonstrated that the duplex TiN-MAO coating possessed more noble Ecorr value with lower passivation current density of 8.91 × 10−7 A·cm−2 comparing with the MAO-coated substrate in reducing acid electrolyte. Furthermore, the tribocorrosion results indicated that the synergistic effect of wear and corrosion resulted in severe abrasive and adhesive wear for the bare and MAO-coated substrates. However, the duplex TiN-MAO coating presented the best anticorrosion and antiwear performances with the lowest CoFs value (approximately 0.17) and wear rate (approximately 6.21 × 10−5 mm3·N−1·m−1) obtained simultaneously under cathodic protection.