Electrodeposited Co-Ni Powders

2 Anomalous Codeposition of Alloy Powders 8.2.1 Electrodeposited Co-Ni Powders 

1 Polarization Curves for Co-Ni Alloy Powder Electrodeposition from the Sulfate-Containing Supporting Eiectroiyte 

In Fig. 8.1a are shown polarization curves corrected for IR drop for the processes of Co, Ni, and Co-Ni alloy powder electrodeposition from 1 M (NH4)2S04 + 0.7 M NH4OH containing supporting electrolyte. Their shape of aU polarization curves is identical, characterized with two inflection points, A and B. For Co electrodeposition, sharp increase of current occurs at about —1.19 V versus Ag/AgCl, while for Ni electrodeposition, this phenomenon is moved to more negative potentials 

2 The Morphology of the Co-Ni Alloy Powders Electrodeposited from the Sulfate-Containing Supporting Electrolyte 

The morphology of the Co-Ni alloy powders electrodeposited at the current density i = —0.5 A cm from the electrolytes containing different Ni VCo ions ratio is shown in Figs. 8.2, 8.3, 8.4, and 8.5. It is obvious that the morphology of Co-Ni alloy powder is sensitive to the Ni /Co ions ratio, i.e., to the composititMi of the alloy powder. 

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