Improvement of bonding strength of AZ31B magnesium alloy by anodizing and chromium-free conversion treatments

Abstract

The influences of chromium-free chemical conversion treatment and anodizing treatment on bonding strength of AZ31 magnesium alloy were studied by lap-shear test, SEM and electrochemical methods. Both chemical conversion treatment and anodizing can increase the bonding strength. The anodizing treatment gives higher bonding strength and better corrosion resistance than chemical conversion treatment. The increase of bonding strength by the treatments may be attributed to the uneven surface structures with micro-pores, resulting in increased bonding areas and the embedding effect.

Keywords

magnesium alloy / adhesive bonding / chemical conversion treatments / anodizing

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