Mechanism of Al Alloy Corrosion and the Role of Chromate Inhibitors

Abstract

This report summarizes a 5-year MURI program focused on the mechanism of corrosion inhibition of Al alloys by chromates. This involves understanding how chromate acts in organic primer coatings, in conversion coatings on Al alloys, and in solution as a dissolved species. Other work was concerned with the mechanisms of Al alloy corrosion even in the absence of chromate. The findings have addressed the formation mechanism of Cr-containing surface layers, the structure and composition of those layers, the release of chromate from those layers, the migration of chromate to active corrosion sites, and the mechanism by which chromate inhibits the corrosion. Cr-containing films were found to be an effective cathodic inhibitor, even at monolayer amounts. Such films also inhibited breakdown, and are therefore also anodic inhibitors.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2001
Accession Number
ADA399114

Entities

People

  • Gerald S. Frankel

Organizations

  • Ohio State University

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Aluminum Alloys
  • Chemical Compounds
  • Chemical Synthesis
  • Chemistry
  • Chromium Compounds
  • Corrosion
  • Corrosion Inhibition
  • Corrosion Resistance
  • Inhibition
  • Inhibitors
  • Material Degradation Processes
  • Materials
  • Materials Science
  • Measurement
  • Photochemical Reactions
  • Spectra
  • Substrates

Fields of Study

  • Materials science

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Surface Coatings Technology.