The role of corrosion product deposition in galvanic corrosion of aluminum/carbon systems

Autor: Joseph Hoffman, Eva Hakansson, Maciej Kumosa, Paul Predecki
Rok vydání: 2017
Předmět:
Zdroj: Corrosion Science. 114:10-16
ISSN: 0010-938X
Popis: This study is concerned with the role of corrosion product deposition in the galvanic corrosion between aluminum and Carbon Fiber Reinforced Polymer matrix composite (CFRP). The galvanic corrosion of a high voltage conductor assembly consisting of a cylindrical CFRP rod surrounded by tightly wound aluminum wires has been investigated through experimental work and modeling. The main corrosion product is Al(OH)3, which presents as a gelatinous substance in the crevices between the Al wires. The formation of Al(OH)3 was observed to coincide with the decay in the galvanic corrosion current. A new analytical model was developed to investigate if the decay could be caused by corrosion products restricting the transport of oxygen to the cathode. Modeling of the oxygen diffusion through the deposited corrosion products generated galvanic corrosion rates that agreed well with the experimental measurements after an early exponential decay period. The findings suggest that the corrosion product deposition may be the most important galvanic corrosion rate controlling mechanism in this geometry and similar geometries.
Databáze: OpenAIRE