Corrosion inhibition of aluminum and aluminum alloys by soluble chromates, chromate coatings, and chromate-free coatings

M. W. Kendig, R. G. Buchheit

Research output: Contribution to journalArticlepeer-review

450 Scopus citations

Abstract

This review covers the aqueous chemistry of chromium and the origins of chromium toxicity. Evidence from older and more recent studies is presented showing that inhibition of Al corrosion is derived from both inhibition of oxygen reduction and inhibition of metal dissolution reactions mainly due to a delay in the onset of pitting. Inhibition of corrosion by chromates appears to be closely linked to their ability to irreversibly adsorb on to metal and oxide surfaces. With respect to chromate conversion coatings (CCCs), the evolution of modern coating formulations is presented with a focus on key advances that led to process simplification and improved coating performance. The current understanding of CCC formation, protection, and aging is presented. In the last section of the paper, processing and properties of selected chromate- free conversion coating chemistries is discussed. This discussion focuses on coatings that offer particularly attractive attributes such as self-healing and excellent adhesion.

Original languageEnglish
Pages (from-to)379-400
Number of pages22
JournalCorrosion
Volume59
Issue number5
DOIs
StatePublished - May 2003

Keywords

  • Aluminum
  • Chromate conversion coatings
  • Chromate-free conversion coatings
  • Chromium
  • Inhibition
  • Metal dissolution
  • Oxygen reduction

ASJC Scopus subject areas

  • General Chemistry
  • General Chemical Engineering
  • General Materials Science

Fingerprint

Dive into the research topics of 'Corrosion inhibition of aluminum and aluminum alloys by soluble chromates, chromate coatings, and chromate-free coatings'. Together they form a unique fingerprint.

Cite this