Study the existing form of copper (p-type oxide/segregation) and its release mechanism from the passive film of Ti-7Cu alloy

The existing form of copper and its release mechanism from the passive film Ti-7Cu alloy was studied by Quantitative analysis depth profile series electrochemical tests. Results were interpreted within Point Defect Model-II. Copper does not any p-type (cuprous or cupric) oxide but preferentially oxidises at metal/film interface segregated as Cu interstitials Cui+ become substituted CuTix' in oxygen-deficient TiO2-x barrier layer having n-type semiconducting character. Eventually, species dissolute through ions into solution film/solution via Esaki-tunnelling effect.