Published 01/28/2013

BOOK REVIEW: Electrochemical Production of Metal Powders

S S Djokic (Ed) Vol. 54 in Series. “Modern Aspects of Electrochemistry” Publ.

Electroplating

Anselm Kuhn, Metal Finishing Information Services

For almost 60 years, successive volumes of “Modern Aspects of Electrochemistry” have showcased the frontiers of this subject. Some volumes include a range of topics, while others, such as this one, are themed. The production of metal (or alloy) powders by electrodeposition, usually from aqueous solutions, is a rather specialized branch of electroplating, operating at or beyond the region of limiting current density, where no sane conventional electrodepositor would ever dream of venturing. This is “burnt deposit” territory!

As the Editor notes, this is the first book on the subject in English since the work of Calosaru back in 1979. The book comprises seven chapters. The first is an excellent exposition of the mechanism of electrochemical powder formation, arguably the best currently in print. There follow chapters on electrochemical powder formation of specific metals and alloys, including Ag, Pd, Pb, Cd, Fe, Co and Ni as well as alloyed powders, Co-Ni, Fe-Ni and Mo-Ni-O. Copper powders have a chapter to themselves. All are written by experts in the field. The last two chapters deal with production of nanoparticles and what we would call “electroless” powder formation. Each chapter is liberally illustrated with micrographs showing powder particle morphology, together with X-ray spectra, polarization plots and related electrochemical and material properties data.

In terms of its content, this book could hardly be more authoritative. However there is, unfortunately, much that is omitted. Metal powders appear to be an increasingly important feedstock for advanced technologies such as 3D rapid prototyping or printing of electronic circuits, as well as in manufacture of electronic materials. As such, the three main routes for their manufacture are high-temperature, molten metal methods, together with chemical and electrochemical reduction. The particle size distributions and morphologies from each of these routes are very different.

The book lacks a “scene setting” introduction to allow readers to put these routes into context. There is a whole branch of industry engaged in the manufacture of metal powders by electrodeposition, and this industry is nowhere described. In his preface, the editor asserts that the work will be of interest to electrochemical engineers and one questions this, for the work contains no single description of electrochemical cells for carrying out these processes. The whole technology of rotating cylinder cathodes (scraped or not) is absent. Electrochemical deposition of powders is important in a completely different field, namely recovery of metal ions from electroplating wastewaters using plating barrel technology, again, this is not covered. Lastly, although each chapter has numerous references, they relate only to those metals or alloys described in those chapters. Thus I searched in vain for the work of Neufeld et al, on electrodeposition of silver-tin alloy powders and many other publications were presumably seen as outside the scope of this work.

In conclusion, for readers with a specific interest in the metals that are covered, one could certainly recommend this work (or perhaps a download of a specific chapter). However for anyone contemplating setting up their own production plant – which could be a lucrative line of business, there is little here to set them on their way.