Aj. Aldykiewicz et al., THE INVESTIGATION OF CERIUM AS A CATHODIC INHIBITOR FOR ALUMINUM-COPPER ALLOYS, Journal of the Electrochemical Society, 142(10), 1995, pp. 3342-3350
In situ current density mapping, scanning electron microscopy, and ene
rgy dispersive spectroscopy were used to study the effects of cerium a
s a corrosion inhibitor for an aluminum copper alloy (Al 2024-T4) in c
hloride containing solutions. It was found that cerium inhibits corros
ion of this alloy by reducing the rate of the cathodic reaction. This
was due to the formation of cerium-rich films over copper containing i
ntermetallics which act as local cathodic sites. Results from tests ca
rried out on an aluminum/copper galvanic couple, which was used to sim
ulate the electrochemical behavior of the copper containing intermetal
lics, showed that corrosion inhibition was associated with the formati
on of a Ce-rich film over the copper in agreement with that observed f
or the alloy.