Effect of aging on corrosion and discharge performance of AZ63-1.5RE alloy as anode in magnesium-dissolved oxygen seawater batteries

• Published in: Journal of power sources 2023-10, Vol.581, p.233405, Article 233405
• Main Authors: Abedini, Amin, Shamskhani, Reza, Ebrahimi Valmoozi, Ali Asghar, Seyyed Afghahi, Seyyed Salman
• Format: Article
• Language: English
• Subjects: Anode; Corrosion; Dissolved oxygen seawater– magnesium battery; Lanthanides; Magnesium
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2023.233405

This study aims to understand how aging treatment affects corrosion resistance and discharge performance of AZ63-1.5mischmetals Rare earths (AZ63-1.5RE) alloy in low-power dissolved oxygen seawater batteries. Solutionizing and aging treatment at 180 °C, 210 °C, and 240 °C for 16 h, 20 h, and 24 h is used to investigate the effects of heat treatment on corrosion and discharge performance. An XRD pattern of alloys after solutionization and aging indicates a change in crystalline orientation and an increase in Mg phases proportion. A reduction in self-corrosion of alloys is achieved through solutionizing and aging. With solutionizing and aging of the alloys, their discharge potentials is shifted to more negative values by about 0.01–0.02 V. The anodic efficiency also is improved significantly from 53.89% for the as-cast alloy to 67.55% for the aged alloy at 210 °C for 20 h. Following 24 h of discharge, the aged alloy at 210 °C demonstrated the highest polarization resistance. The favorable corrosion performance can be attributed to grain refinement of the β-Mg17Al12 phase, the increased contribution of the Al-RE corrosion-resistant phase, the low contribution of the layered phase in the matrix, and the formation of dense discharge products on the surface. •How aging affect corrosion resistance of AZ63-1.5RE alloy in seawater solution.•Solution treatment reduces the number of β-Mg17Al12 phase particles in Mg grains.•Aging treatment improves grain refinement from β-Mg17Al12 but no Al-RE phase.•Aged alloy provide low self-corrosion resistance and high anodic efficiency.•Dense discharge products with thin cracks on the alloy given high energy density.