Corrosion behaviour of Anodised PM Aluminium Matrix Composite Reinforced with 15 wt % Saffil Alumina short fibre

Abstract

A study of corrosion behaviour on anodised PM aluminium matrix composites (AMC) reinforced with Saffil™ alumina short fibre was done. AMC was fabricated by powder metallurgy methods (PM) with using Al flake powders and Saffil™ alumina short fibres. AMC reinforced with 15 wt % Saffil™ alumina short fibre was selected because it showed optimum mechanical and physical properties. Sulphuric acid anodising process was performed to anodise this AMC. The anodising process was carried out with anodising voltage of 18 V and 15 % vol. H2S04 in anodising time of 60 minutes at room temperature. Corrosion test was done in 3.5 % NaCl solution using electrochemical polarisation measurement based ASTM G5 1999. Scanning electron microscope (SEM) was used to investigate corrosion effects on anodised PM aluminium matrix composite. From the observation, the anodising can reduce corrosion reaction rate on PM aluminium matrix composite. SEM showed that corrosion affected to anodised and non-anodised PM aluminium matrix composite. This research was found that H2S04 anodising was able to give good coating and better corrosion resistance to PM AMC reinforced with 15 wt% Saffil™ alumina short fibre.