Characterization of Spontaneously Formed Cerium-Based Conversion Coatings on Aluminum


Cerium oxide-based conversion coatings for aluminum alloys have been prepared by a spontaneous reaction between aluminum alloy test panels and a solution containing CeCl3. The effects of panel pre-treatment prior to coating, panel orientation in the coating solution, and coating time on coating morphology and performance were examined. Coating performance was evaluated by using ASTM B117 salt fog testing, and the optimal coating time was found to be between five and ten minutes. Coating morphology was characterized using scanning electron microscopy (SEM). Coatings that were deposited on the downward facing side of test panels pre-treated by desmutting, degreasing, and acid activation performed well in salt fog testing. Coatings that performed well in salt fog testing consisted of cerium-rich spherical nodules approximately 250 nm in diameter embedded in a featureless cerium-containing matrix.

Meeting Name

26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: B (2002: Jan. 13-18, Cocoa Beach, FL)


Materials Science and Engineering

Keywords and Phrases

Aluminum alloys; Cerium compounds; Morphology; Scanning electron microscopy; Acid activation; Cerium oxide-based conversion coatings; Degreasing; Desmutting; Salt fog testing

International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


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© 2002 Wiley-Blackwell, All rights reserved.

Publication Date

01 Jan 2002