Electrochemically-induced TiO2 incorporation for enhancing corrosion and tribocorrosion resistance of PEO coating on 7075 Al alloy
- Autori: Akbari, Ehsan; Di Franco, Francesco; Ceraolo, Paolo; Raeissi, Keyvan; Santamaria, Monica*; Hakimizad, Amin
- Anno di pubblicazione: 2018
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: A. aluminium; B. EIS; B. polarization; B. SEM; C. anodic films; C. oxide coatings; Chemistry (all); Chemical Engineering (all); Materials Science (all)
- OA Link: http://hdl.handle.net/10447/339544
Abstract
7075 Al alloy was PEO-treated in a silicate based electrolyte containing 3 g l-1 potassium titanyl oxalate using unipolar and bipolar pulsed current waveforms. The coating formed by the bipolar waveform with the wider cathodic pulses showed volcano-like surface morphology with no evidence of large pores at the metal/coating interface. It revealed the highest corrosion performance due to the synergistic effect of TiO2 incorporation and structural/morphological features along with a better passivation behavior indicating no pitting susceptibility. For this coating, the tribocorrosion tests showed no potential drop during sliding under 1 N with the lowest volume loss of 0.022 mm3.