The corrosion of two aluminium sacrificial anode alloys in SRB-containing sea mud

• Corrosion rate of Al–Zn–In–Sn was higher than Al–Zn–In–Mg–Ti in SRB sea mud.
• Pitting of Al–Zn–In–Sn occurred in sea mud with and without SRB.
• More serious corrosion damage occurred in the SRB-containing sea mud.
• The growth rates of pits could be further increased in the presence of SRB.
• Corrosion rates of anodes increased with SRB because of cathodic depolarisation.

Corrosion of two sacrificial anodes in marine sediment with and without sulphate-reducing bacteria (SRB) was performed. Weight loss experiments indicated that the corrosion rate of Al–Zn–In–Sn was 2–3 times higher than that of Al–Zn–In–Mg–Ti in the SRB-containing sediment. Electrochemical analysis suggested that the corrosion rates of the two anodes were enhanced substantially by SRB. Surface analysis revealed the localised corrosion of the two sacrificial anodes in abiotic and biotic sediments. The concentration of Al3+ in the surface of the samples immersed with SRB was lower than that of the samples without SRB.