The Passivity of Electrodeposited Iron-Nickel-Chromium Alloys

Abstract
Polarisation curves have been plotted for iron-nickel-chromium alloy coatings prepared by electrodeposition from a number of solutions. Although most specimens become passive in 0·1 M Na2SO4 during anodic polarisation, in all cases the passive current densities are much higher than those for stainless steels and the large active peaks suggest that these alloys will only become passive spontaneously under strongly oxidising conditions. Studies by electron microscopy and X-ray diffraction suggest reasons for this behaviour, but the very fine grain size of deposits of this type precludes any accurate structural analysis.