Study on Corrosion Behavior of Al/Mg/Al Laminated Metal Composites in Sodium Hydroxide Solution of Different pH

ABSTRACT The corrosion behavior of Al(1060)/Mg(AZ31B)/Al(1060) laminated metal composites (LMCs) in alkaline sodium hydroxide solution with three pH values at room temperature was investigated by electrochemical and morphological characterization methods. The results clearly show that the galvanic effect enhances the corrosion of AZ31B at pH = 10. The increase in pH changes the polarity of AZ31B and 1060. The passivation of magnesium in sodium hydroxide leads to the change of surface state and the increase of potential on the side of AZ31B magnesium alloy, and the side of 1060 aluminum alloy as the anode is the superposition of galvanic corrosion and self‐corrosion.