The effect of in-situ reactive incorporation of MoOx on the corrosion behavior of Ti-6Al-4 V alloy coated via micro-arc oxidation coating

Abstract In an attempt to examine the impacts of molybdenum oxides (MoOx) on the corrosion behavior of Ti-6Al-4 V alloy, a series of micro-arc oxidation (MAO) coating was conducted in a solution containing Ca and P ions without and with two different concentrations of Na2MoO4, such as 0.01 and 0.04 M. Although Na2MoO4 addition increases the porosity in the coating, highly chemical stable MoOx in the oxidation state of +4 and +6 referred to MoO2 and MoO3, respectively, were successfully incorporated into the coating layer, which could be responsible for the remarkable improvements in the electrochemical stability of the coating.