Topic: problem on small anode area

What are the problems related to small anode area ?

For example nickel solution is depleted more fast and the coating is brittle because the oxide formed?

where this oxide come from?



Re: problem on small anode area

Small anodes themselves are nto problematic. It is the ratio of anode to cathode that is a better indicator of a problem. I will assume that you mean to ask about the effects of a low anode to cathode ratio.

In electroplating, the formation of gas on the anode and cathode is a part of the process. The anode usually releases oxygen gas. When you have sufficient surface area, the rate of the reaction is slow enough to minimize the oxidation of the anode material. However, with a small anode:cathode ratio, the rate is increased. There is more oxygen present, which drives the reaction towards the formation of metal oxides. And this only gets worse, as the oxides are usually poor conductors, forcing more current through the un-oxidized anode material, which then gets oxidized, etc, etc, etc.

Low anode ratio also can cause quick metal depletion from the bath and non-uniformity of the deposit (especially on larger parts, as the anode to cathode distance becomes highly variable), to say the least.

-Dustin Gebhardt, CEF

Advanced Manufacturing/Finishing Engineer


Sanford, NC