Lithium nitrate salt-assisted CO 2 absorption for the formation of corrosion barrier layer on AZ91D magnesium alloy

Mg alloy corrosion susceptibility is a major issue that limits its wide industrial application in transport, energy and medical sectors. A corrosion-resistant layer containing crystalline MgCO was formed on the surface of AZ91D Mg alloy by Li salt loading and thermal CO treatment. Compared to the uncoated AZ91D surface, the surface layer exhibited up to a ∼15-fold increase in corrosion resistance according to the electrochemical results in 3.5 wt% NaCl solution and ∼32% decrease in wear rate compared to untreated AZ91D. The improved corrosion resistance is attributed to the formation of a