The AA7075–CS1018 Galvanic Couple under Evaporating Droplets

The galvanic corrosion behavior of the AA7075–CS1018 couple was examined in dynamic electrolytes using the ZRA technique. A modified electrochemical setup was developed to support the use of thin-film gel and liquid electrolytes on metallic surfaces. This allowed the collection of chemical informati...

Full description

Bibliographic Details
Main Authors: Marvin Montoya, Juan Genesca, Rodrigo Montoya
Format: Article
Language:English
Published: MDPI AG 2024-03-01
Series:Corrosion and Materials Degradation
Subjects:
Online Access:https://www.mdpi.com/2624-5558/5/1/5
Description
Summary:The galvanic corrosion behavior of the AA7075–CS1018 couple was examined in dynamic electrolytes using the ZRA technique. A modified electrochemical setup was developed to support the use of thin-film gel and liquid electrolytes on metallic surfaces. This allowed the collection of chemical information, left behind by the liquid electrolyte during evaporation, through a thin-film gel. The analysis of the gel electrolyte film confirmed the acidification on AA7075 and the alkalinization on CS1018 but also offered novel insights on their dependence on the galvanic current. The galvanic current was proportional to the initial NaCl concentration in the range of 0.01 to 0.06 M. However, due to continuous evaporation, the NaCl concentration increased, limiting oxygen diffusion and decreasing the galvanic current, especially for electrolytes exceeding 0.06 M. The galvanic current was determined by considering the dynamic evolution (caused by the evaporation of the electrolyte film) of both the thickness of the electrolyte and its concentration.
ISSN:2624-5558