Synthesis and Characterization of Chrom-Free Dark Coating on AA6063 Aluminium Alloy with K₂ZrF₆

Abstract:

A new passivation process has been developed for producing a chrome-free and coloured conversion coating on aluminium alloy AA6063 with K₂ZrF₆. The conversion coating obtained has a dark film, which enables visual assessment of the coating development and coating quality during processing. The colouring effect is a significant advantage over the zirconium based conversion coatings currently used in the industry, which are largely colourless. The new treatment process is simple and allows a uniform coating to be formed within a few minutes. The composition and the surface morphology of the coatings were characterized. The corrosion resistance of the coated samples was evaluated by electrochemical tests. Through electrochemical analysis, corrosion current of the coatings is low, it has excellent corrosion resistance; SEM, EDS and XRD are used to analyze the process coating.

• Periodical: Advanced Materials Research (Volume 1053)
• Pages: 421-428
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1053.421
• Online since: October 2014
• Authors: Ting Yi Chen*, Ye Qi Fu, Wen Lu, Wen Fang Li
• Keywords: Aluminum Alloy 6063, Chrome-Free Conversion, Coloring, Electrochemical Detection, Zirconium Porous Film

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