Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638390
Title: Localised corrosion of AA2024
Author: O'Driscoll, S.
Awarding Body: University of Wales Swansea
Current Institution: Swansea University
Date of Award: 2004
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Abstract:
Novel electrochemical techniques, Scanning Vibrating Electrode (SVET) and Scanning Kelvin Probe (SKP), have been used to characterise pitting and filiform corrosion characteristics of aerospace alloy 2024-T3/T351. They have also been used to semi-quantify the inhibition efficiencies of chromate and trivalent Rare Earth Metal (REM) salts (cerium, lanthanum, and yttrium), both in solution and in coatings. It is shown that after long periods (hours) of immersion in 3.5% aqueous NaCl stable pitting occurs, these pits are believed to be in the form of interconnected tunnels, emerging at various points on the surface. It is also shown that chromate is the most effective inhibitor of those tested, both in solution and in coatings. The role of S phase intermetallic particles on the pitting corrosion of the alloy has also been investigated using SVET, and secondary and back-scatter electron microscopy. It is shown that the pitting corrosion rate exhibited by the alloy increases with the increase of fractional surface area occupied by precipitate. It is also shown that, when a non-uniform distribution of intermetallic particles is present, the maximum density of stable corrosion pits coincides with the minimum surface density of intermetallic particles.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.638390  DOI: Not available
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