Regular Article

Effect of hot rolling on the corrosion behavior of AZ31 magnesium alloy

¹ Physics and Chemistry of Materials Laboratory, Department of Physics, University Mohamed Boudiaf, 28000 M’sila, Algeria
² Department of Physics, University Mohamed Boudiaf, 28000 M’sila, Algeria
³ Inorganic Materials Laboratory, Department of chemistry, Faculty of Sciences, University of Mohamed Boudiaf, 28000 M’sila, Algeria
⁴ Faculty of Physics, USTHB, BP32 El-Alia, Dar El-Beida, Algiers, Algeria
⁵ Nuclear Research Center of Birine, Ain-Oussera, Djelfa, Algeria
⁶ Centre de Développement des Technologies Avancées, CDTA, Cité du 20 août 1956, Baba-Hassen, 16303 Algiers, Algeria

^* e-mail: azehibou@yahoo.fr

Received: 12 March 2018
Accepted: 4 May 2018

Abstract

The aim of the present study is to investigate the effect of deformation conditions on the corrosion behavior of AZ31 (Mg-3Al-1Zn, % wt.) in 0.9% NaCl (wt.%) solution. The AZ31 alloy was hot rolled at 360 °C to 20 and 50% of thickness reduction. Electrochemical measurements were used to study the corrosion behavior of AZ31 alloy. Analysis of corrosion products after immersion test was performed using optical microscopy, X-ray diffraction and Raman spectroscopy. The mechanical properties of corroded samples were investigated using tensile test at room temperature. Results indicated that the corrosion rate was strongly affected by the hot rolling level. A lower corrosion potential and reduced polarization resistance was observed after hot rolling compared to the as received AZ31 alloy. The corrosion product was evidenced mainly as Mg(OH)₂ compound exhibiting a filiform-like morphology. Apparently, the corrosion improved the room temperature ductility of AZ31 alloy.