Modeling the Galvanostatic Pulse and Pulse Reverse Plating of Nickel‐Iron Alloys on a Rotating Disk Electrode

Abstract

A model incorporating mass-transfer effects, electrode kinetics, and homogeneous reaction is presented to describe galvanostatic pulse (PC) and pulse reverse (PR) plating of nickel-iron alloys from a sulfate bath onto a rotating disk electrode. It has been satisfactorily fit to experimental data taken from the literature and then used to investigate the effects of pulse mode and pulse parameters and to compute the transient responses of the partial current densities and concentration profiles. A comparison of the effect of pulse mode on plating confirmed previously reported evidence that PC plating tends to produce alloys with similar iron content to those obtained by dc plating, particularly at high current. PR plating has been shown to be the most effective method of controlling iron content in the alloys. By increasing the ratio of the anodic pulse amplitude to the cathodic pulse amplitude, the extent of anomalous codeposition and the sensitivity of alloy composition to the applied current can be reduced. Analysis of the transient partial current densities confirmed experimental evidence that this improvement is due to preferential dissolution of iron during the anodic pulses. Model DevelopmentThe following assumptions have been made in the development of the model: (i) edge effects on the RDE are not considered and only transport in the direction normal to

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“…The discussion is centered on the axial flow along the central axis (r = 0) since this is the commonly used velocity profile employed in modeling studies based on the Cochran equation (e.g. [19,23,22,25,24,21].…”

“…When the velocity profile is known, in fact, it is possible to model the system (e.g. [19,[23][24][25]) and determine the kinetic constants from the experimental data (e.g. [21,22]).…”

The effect of Fe3+ on magnetic moment of electrodeposited CoFe alloys—Experimental study and analytical model

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Applications to Magnetic Recording and Microelectronic Technologies

“…For typical frequencies of the paddle (v < 0.7 Hz) and H/h < 1.2, the constant a is $0.22 [27], and the values of the constants p and m in the exponents could be taken approximately as 0.33 and 0.61 [27,28]. The representative values of the ion diffusivities that could be used in these calculations are given in Table 27.3 [18,29,30].…”