Mechanistic study of aluminum alloy corrosion under the interaction of Embellisia sp. and Candida xyloterini†

Microorganisms and their cultural traits significantly affect the service performance and durability of materials. Currently, research on the corrosion mechanisms of microorganisms affecting aluminum alloys primarily focuses on bacterial corrosion, with fewer studies addressing the corrosion behavior and mechanisms caused by fungi. This study investigated the corrosion behavior of aluminum alloys under the interaction of two fungi, Embellisia sp. and Candida xyloterini, as well as their composite systems. Electrochemical impedance analysis revealed that both fungi inhibited the corrosion of aluminum alloys, with the degree of inhibition ranking in descending order as follows: Embellisia sp., mixed systems, and C. xyloterini. The main reasons for the inhibition of corrosion were the aerobic nature of the two fungi and the formation of a composite membrane structure on the metal surface, which consisted of both the corrosion product film and the biofilm. Fungal growth curves indicated that the co-culture led to a reduction in the number of fungi, resulting in a decrease in biofilm density and resistance to corrosive ions. Consequently, the two fungi exhibited an antagonistic effect in inhibiting the corrosion of aluminum alloys.