Al-Mg alloys prepared by mechanically alloying reinforced with carbon nanotubes and their corrosion behavior in bioethanol

Abstract

Two different Al-Mg alloys containing 4 and 6 wt. % Mg were mmechanically produced and reinforced with 0.05 wt. % Carbon nanotubes (CNT) and corroded in fuel grade bioethanol (FGB). Employed techniques for the corrosion tests included potentiodynamic polarization curves, linear polarization resistance and electrochemical impedance spectroscopy measurements. Results have shown that there was no evidence of the formation of a passive layer on top of the specimens. Corrosion rate increased with the increase in the Mg contents and the addition of CNTs. Specimens exhibited a type of localized corrosion similar to pits, which increased in number, size and depth with the addition of Mg and CNTs in the alloys.