The Positive impact of biomineralization for marine corrosion protection of AA5083 alloy

This paper investigates, using surface characterisation techniques (SEM, XPS and ToF-SIMS), the impact of marine biological activity on AA5083 corrosion behaviour during seawater immersion. Different solar exposure (light vs. dark) results in distinct marine fouling development, influencing surface modifications. On the dark side, an Al/Mg oxide/hydroxide layer forms, allowing Cl- penetration. Pitting attack is observed after immersion. For the light side, a dual layer structure forms, with a hydrated Mg rich outer layer, showing barrier effect to Cl- penetration. No localized corrosion occurs. A comparison with abiotic conditions demonstrates the corrosion-inhibiting effect of marine biological activity on AA5083. [Display omitted] •Marine biological activity has a corrosion-inhibiting effect on AA5083.•Marine fouling, depending on solar exposure, influences Al-Mg surface modifications.•No localised corrosion on the light side and pitting attack on the dark side.•The light side presents a dual layer structure with a hydrated Mg rich outer layer.•The dark side presents an Al/Mg oxide/hydroxide layer allowing Cl- penetration.