AC impedance studies of aluminum alloy 6061 in chloride solutions: The role of oxygen, hydrogen ions, and aluminum ions in initiating crevice corrosion

Journal Article · Mon Jun 01 00:00:00 EDT 1987 · J. Electrochem. Soc.; (United States)

DOI:https://doi.org/10.1149/1.2100674· OSTI ID:6339117

Reising, R F

The purpose of this research was to determine whether oxygen molecules, hydrogen ions, or aluminum ions initiate the crevice corrosion of aluminum alloy 6061 in aqueous chloride solutions. Corrosion-potential and ac-impedance measurements show that pH is the dominant factor in accordance with the crevice-corrosion mechanism. It is further proposed that crevice corrosion occurs because film breakdown mechanisms prevail over film repair mechanisms in the crevice when the pH drops to values near 4. In this pH regime aluminum ion dissolution is thermodynamically favored over insoluble aluminum oxide formation at the solution-solid interface.

• Research Organization: General Motors Research Labs., Physical Chemistry Dept., Warren, MI 48090
• OSTI ID: 6339117
• Journal Information: J. Electrochem. Soc.; (United States), Vol. 134:6, Issue 6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
CORROSION
CHLORIDES
CORROSIVE EFFECTS
ALTERNATING CURRENT
ALUMINIUM COMPOUNDS
AQUEOUS SOLUTIONS
DISSOLUTION
ELECTRIC IMPEDANCE
FILMS
HYDROGEN COMPOUNDS
IONS
OXYGEN
PH VALUE
QUANTITY RATIO
ALLOYS
CHARGED PARTICLES
CHEMICAL REACTIONS
CHLORINE COMPOUNDS
CURRENTS
DISPERSIONS
ELECTRIC CURRENTS
ELEMENTS
HALIDES
HALOGEN COMPOUNDS
IMPEDANCE
MIXTURES
NONMETALS
SOLUTIONS
360105* - Metals & Alloys- Corrosion & Erosion