Study of corrosion inhibition of coupled Al2Cu–Al and Al3Fe–Al by cerium cinnamate using scanning vibrating electrode technique and scanning ion-selective electrode technique

Abstract

The galvanic corrosion of the coupled Al2Cu and Al as well as Al3Fe and Al in 0.005M NaCl in and without the presence of cerium cinnamate was studied. Scanning vibrating electrode technique and scanning ion-selective electrode technique were used to measure the distribution of current densities and pH. The results indicate that cerium cinnamate played inhibiting effect on the coupling corrosion of Al2Cu–Al and Al3Fe–Al. For Al2Cu–Al, the inhibition was mainly influenced by the production of cerium oxide/hydroxide on Al2Cu surface. However, for Al3Fe–Al, the inhibition was mainly influenced by the adsorbed cerium cinnamate on the Al3Fe surface.