| The effects of the solution chemistry on the structure and properties of electrogalvanized steel from a sulfate electrolyte were studied.;Increasing antimony additions decreased the grain size, made the nucleation more progressive and less uniform in coverage. The change in the morphology and the orientation was apparent even at 1 mg/;The presence of lead in the electrolyte caused poor adhesion of the deposit upon heating, with the duration of heating necessary to enduce peeling being dependent upon the temperature and the plating parameters. Polarization studies on a rotating disc electrode were used to measure the diffusion coefficient of lead in the electrolyte. The method could be used to study the rate of lead deposition or the mass transport characteristics of the electrogalvanizing system.;Of the conductivity enhancing additions, sodium, ammonium and potassium sulfate, the best compromise between conductivity, viscosity, current efficiency and bath stability was provided by sodium sulfate. The tendency of these additions was to change the predominant crystallographic orientation of the zinc to (101) and a concomitant change in the deposit morphology. |
