Effect of benzylideneacetone on the electrodeposition mechanism of Zn–Co alloy
Résumé
The influence of benzylideneacetone (BA) on the mechanism of Zn–Co alloy electrodeposition onto AISI 1018 steel was studied in chloride acidic solutions. Results indicate that BA modifies the exchange current densities of zinc and cobalt such that the alloy is electrodeposited via a normal codeposition mechanism. Analysis of the deposits by Auger spectroscopy and X-ray diffraction shows that BA increases the cobalt concentration in the electrodeposited alloys and gives deposits with a constant concentration profile of both Zn and Co. BA also inhibits the formation of zinc hydroxide in the initial deposition stages, which supports the proposed mechanism of normal codeposition. Finally, it is shown that BA modifies the morphology of the deposits by inducing a reduction in the cluster size, leading to compact, smooth and shiny coatings.