The corrosion behaviors of Mg-3Nd alloy in Qinghai Lake water

The corrosion behaviors of Mg-3Nd alloy in Qinghai Lake water (Cl − , SO 4 2− , HCO 3 − , CO 3 2− ) were studied, focusing on synergistic anion effects between Cl − and HCO 3 − . HCO 3 − demonstrates dual roles in Mg alloy corrosion mechanisms: it induces localized micro-galvanic coupling effects that exacerbate anodic dissolution during initial exposure, while facilitating the progressive formation of a composite Mg(OH) 2 /MgCO 3 passivation layer through interfacial precipitation reactions during long-term immersion. Cl − induced interfacial degradation triggers lamellar spallation of Mg(OH) 2 /MgCO 3 layers. The results revealed the competitive effects of anion interactions and transient protective phase MgCO 3 on corrosion behaviors of Mg alloy, providing insights for the design of corrosion-resistant lightweight equipment in salt-lake water environments.