Anodising of Aluminium Alloy Plates from Different Series Produced by Rheo-High Pressure Die Casting

Abstract:

Anodising of aluminium alloy components can be used for decorative purposes and to enhance the corrosion and wear resistance. In this research, four different Al-alloy series namely Al-Cu-Mg (2xx/2xxx), Al-Si-Mg (3xx), Al-Mg-Si (6xxx) and Al-Zn-Mg-Cu (7xxx) were used to produce plates by rheo-high pressure die casting (R-HPDC). Castings produced by R-HPDC suffer from a surface liquid segregation (SLS) phenomena. This surface layer is enriched with alloying elements and it is shown to have different characteristics as compared to the bulk material. The study focused on the anodisability of plates from the four series produced by R-HPDC with and without the SLS. The samples were anodised at a commercial facility. The oxide layer thickness and homogeneity were studied using optical microscopy.

• Periodical: Solid State Phenomena (Volumes 217-218)
• Pages: 247-252
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.217-218.247
• Online since: September 2014
• Authors: Levy Chauke*, Heinrich Möller, Gonasagren Govender
• Keywords: Aluminium Alloy, Anodisability, Rheo-High Pressure Die Casting (R-HPDC), Semi-Solid, Surface Liquid Segregation

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