Effect of 10 vol.%SiC reinforcement on the corrosion behaviour of A356 aluminium alloy in basic solutions

In this study, corrosion behaviour of A356-10 vol.% SiC composite and A356 aluminium base alloy was evaluated in NaOH solutions. For this purpose, after immersion of samples at open circuit potential (OCP) for 1 h in solutions for reach the steady state, Tafel polarization measurements were done. The Tafel polarization studies of the A356-10 vol.% SiC composite and the base alloy in NaOH solutions showed that the corrosion rate of the composite is higher than that of the base alloy. Also, the Tafel polarization studies revealed that the corrosion rates of both the basealloy and composite increase with the increase in the concentration of NaOH. The experimental results show that the A356-10 vol.% SiC composite as well as the base alloy do not form the passivation layer in the selected NaOH solutions. The scanning electron microscope (SEM) micrographs of the composite demonstrated significant porosity throughout the specimen and frequent clustering of SiC particles around these pores

کلیدواژه ها:

Aluminium ، Metal matrix composites ، Corrosion ، Electron microscopy ، Casting