The Effect of Machined Surface Condition on the Corrosion Behavior of Magnesium ZM51/SiC Composite

This article studies the effect of surface finish on the corrosion behavior of magnesium ZM51/SiC composite. Four different machining processes were employed: single-point diamond turning, wire electrical discharge machining, grinding, and polishing. The machined surface quality was found to have a significant influence on the corrosion behavior of magnesium ZM51/SiC composite. The results showed that, in terms of corrosion current, charge transfer resistance, and double-layer capacitance, the polished and fine-ground specimens have the highest corrosion resistance whereas the rough-ground specimen exhibited the highest corrosion rate. The effects of the various machining-induced defects on corrosion behavior are discussed.