Is it possible to anodize zinc?

A. Yes it's possible, yes it's radically different -- done at 90 to 200 volts. It is not a decorative finish and colors range from green through grey to brown, but dyeing is not to my knowledge possible. Fred Perlstein had an article in Plating & Surface Finishing March 1979 later reprinted in some AESF Shop Guides entitled "Anodic Coatings for Other Metals". I don't know of any shop doing it although I understand that internal parts of washing machines have had this process done to them in the past.

A. Hello Erin,

Yes it is possible to anodize zinc. But I have yet to actually see a process, or any specifications associated with anodize on zinc. But I have read in numerous differing sources that it is possible, but there was never much more than just that statement.

I'd assume that its functions and possibilities would fall in line with something along the lines of titanium, whereby you can attain color by the use of inorganic coloring functions.

The only issue I'd see with anodizing zinc would be its porosity, and its likeliness to provide a porous and low strength coating.

A. Yes it is possible and was done commercially in the late 1970's, but the problem is the process uses "AC" power, and is quite dangerous without the proper guarding. To my knowledge only one company did provide it commercially, and they stopped offering it many years ago. The biggest benefit was not cosmetic, but corrosion resistant properties; The darker the olive green color, the better the corrosion properties; It gave a dramatic CASS test result; One of the markets was commercial grade marine hardware replacing the steel galvanized castings. But cost was a factor, and it never caught on because alternate materials provided better results at a reduced cost.

A. The main points to aluminium anodising are either/both produce a hardwearing surface / retain dye. For zinc you should examine chloride/carbonate conversion coatings. They are cheap and performed at low temp.