Synthesis and Characterization of Chrom-Free Zr-Ti-Ni Pale Green Coating on AA6063 Aluminium Alloy

Abstract:

With K₂ZrF₆ as the main film-forming material, Ni₂SO₄ • 6 H₂O as colorants, K₂TiF₆ for coloring promoters, chrome-free conversion and treatment for Al6063 at room temperature has been developed, fluid can be of steady function without adding oxidants additionally, fast film forming within 6 minutes. By adding Ni element to make the conversion coating changed from gray to pale green, K₂TiF₆ can promote color and uniform color. Analyzed sample through SEM observation, XPS and XRD analysis, the passivation was composed of Al, Ni, NiZr, Ti and NiZr₃; By electrochemical tests, the corrosion current decreased to 0.067μA of passivation membrane, corrosion resistance increased nearly one hundred times, membrane layer structure circuit is C1 / R1 / (L2 + R2)/(L3 + R3)/(L4 + R4).

• Periodical: Advanced Materials Research (Volume 1053)
• Pages: 414-420
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1053.414
• Online since: October 2014
• Authors: Ting Yi Chen*, Wen Lu, Ye Qi Fu, Wen Fang Li
• Keywords: Aluminum Alloy 6063, Chrome-Free Conversion, Coloring, Electrochemical Detection, Zr-Ti-Ni Porous Film

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