Tm. Harris et J. Stclair, TESTING THE ROLE OF METAL HYDROLYSIS IN THE ANOMALOUS ELECTRODEPOSITION OF NI-FE ALLOYS, Journal of the Electrochemical Society, 143(12), 1996, pp. 3918-3922
With the objective of testing several models of the ''anomalous codepo
sition'' (ACD) encountered in the electrodeposition of nickel-iron all
oys, the effects of bath pH and complexing agents on the composition o
f deposits were examined. When the pH of the ''base line'' bath was in
creased from 3.0 to 5.0, the Ni/Fe mass ratio of the deposit increased
(i.e., the deposition became less anomalous). The presence of tartrat
e ion in the bath produced a slight decrease in the Ni/Fe of the depos
it. This complexing agent complexes ferric ion and thus prevents its p
recipitation but has little interaction with ferrous ion or nickel ion
under the electrodeposition conditions examined. The addition of ethy
lenediamine to the bath produced a significant increase in the Ni/Fe m
ass ratio. This complexing agent does not interact significantly with
ferric ion or ferrous ion under the test conditions. None of these obs
ervations are consistent with the Dahms and Croll model of ACD. The ef
fects of pH and tartaric acid on the deposit composition are consisten
t with the predictions of the Grande and Talbot model and the Matlosz
model. The effect of ethylenediamine is not consistent with the Grande
and Talbot model, but may be interpreted within the framework of the
Matlosz model and the Hessami and Tobias model.