Tribological and oxidation behaviors of the plasma sprayed NiCoCrAlY-Cr2O3-AgVO3 coating

• Tribological properties of NiCoCrAlY-Cr2O3 coating were improved in virtue of liquid-film lubrication of AgVO3.
• Silver vanadate enhances the bond strength of the coating due to its excellent wettability with the powder.
• Silver vanadate has the strong corrosive effect on the NiCoCrAlY-Cr2O3 coating and substrate.

AgVO3 nanowires were prepared and added into the NiCoCrAlY-Cr2O3 coating to improve its tribological properties. The effects of the additive on the microstructure, mechanical properties, high-temperature oxidation, as well as tribological behaviors were investigated. The oxidation and friction-reducing mechanism were also discussed. The results show that the bond strength of the composite coating increased from 34.9 MPa to 44.2 MPa with the addition of AgVO3. The friction coefficient and wear rate of the wear couple were significantly reduced under the AgVO3 lubricating action. But the oxidation resistance of the coating containing AgVO3 was lower than that of the NiCoCrAlY-Cr2O3 coating due to the destructive effect of AgVO3 on the protective oxide scale.