Inhibition effect of alcohols on the aluminum-silicon alloys have been investigated by using electrochemical and surface analysis methods

In this study, the effect of double and triple bonds containing alcohols ( 1-buten- 3-ol, 2-methyl-3-butin-2-ol, 3-methyl-2-buten-l-ol, 3-methyl-3-buten-l-ol, 3 -methyl- l-pentin-3-ol, 5-hexen-l-ol ) on the corrosion of Al-Si alloys have been investigated in H2SO4 and NaCl. The corrosion characteristics of Al-Si alloys have been determined by current-potential curves. By using SEM images from the surface of alloys have been taken in 1 N H2SO4, 1 N HC1 and in addition this solution 20 mM 3-methyl-l-pentyn-3-ol. Results of experimental work shows that corrosion of alloys in HCI and H2SO4 solutions have been effected by elements in alloys such as Cu, Fe. The effect of inhibitors (alcohols) on aluminum alloys show that the corrosion rate of Al alloys has increased following order H2SO4 < NaCl < HCI. This might have changed the activity of alcohols depending on the surface morphology of alloys. In addition, the influence of pyrrole and aforementioned alcohols have, also been investigated by using current-potential curves. Experimental results show that the addition of pyrrole and alcohols in H2SO4 solution have been imported changed passivation potential distance. Also elemental compositions of alloys have directly effected passivation. Especially, this influence is more effective in alloy higher Si % content and less Cu %.Keywords: Aluminium alloys, alcohols, corrosion, inhibition, polypyrol, conducting polymer.