Magnesium alloys are highly susceptible to which form of corrosion?

Magnesium alloys are highly susceptible to pitting corrosion due to their electrochemical properties and microstructural characteristics. Pitting corrosion occurs when localized breakdown of the protective oxide film leads to the formation of small pits on the surface of the metal. Magnesium has a relatively low electrode potential, making it prone to corrosion in chloride environments and areas where the protective film is compromised.

In the case of magnesium alloys, the combination of their high reactivity and the nature of their oxide layer makes them particularly vulnerable to this type of localized attack. Additionally, magnesium alloys often contain alloying elements that can exacerbate pitting by creating variations in the electrochemical potential across the surface, leading to further localized corrosion sites.

Understanding the specific susceptibility of magnesium alloys to pitting corrosion is essential for engineers and materials scientists when selecting materials for applications in corrosive environments, ensuring that protective measures such as coatings or corrosion inhibitors are implemented effectively.