Role of graphene additive on wear and electrochemical corrosion behaviour of plasma electrolytic oxidation (PEO) coatings on Mg–MWCNT nanocomposite

ABSTRACT

In this study, wear and electrochemical corrosion behaviour of as-cast magnesium (Mg)/multiwall carbon nanotube (MWCNT) and plasma electrolytic oxidation (PEO) coated Mg/MWCNT samples were evaluated by dry sliding wear tests and potentiodynamic corrosion tests, respectively. In this respect, Mg/MWCNT composite was manufactured by stir casting route. X-ray diffraction (XRD) analysis shows that the presence of Mg, MgO and Mg₂SiO₄ phases for coated samples. The corrosion rate of the coated samples is about 1.6 times lower than that of un-coated Mg–MWCNT composite. From the wear tests, it is concluded that PEO coating leads to significant improvement in wear resistance in comparison with un-coated Mg/MWCNT composite. It is observed that wear mechanisms are abrasion and oxidation.

KEYWORDS:

• Mg/MWCNT
• nanocomposite
• PEO
• corrosion
• wear

Disclosure statement

No potential conflict of interest was reported by the authors.