As published in Products Finishing Magazine, April 2018 issue.
Alkaline plating baths form carbonates over time, and these carbonates cause the baths to become less efficient, resulting in slower plating speed. Asterion’s Roger Sowinski outlines three options for removing carbonates.
Q. Why is the plating time in my alkaline plating baths increasing? How do I fix this problem?
A. When it comes to plating, time is money, and nothing is more frustrating than your plating bath slowing to a crawl. The good news is that you can return the plating speed to its original levels; the less-than-good news is that it can be quite the chore.
Among the causes of slower plating speeds or loss of efficiency in alkaline plating is the build up of carbonates in the bath. Alkaline plating baths (both cyanide and non-cyanide) will form carbonates over time, and carbonates cause the bath to become less efficient, which manifests itself as a slower plating speed. These carbonates are formed when the alkaline solution is exposed to the carbon dioxide in the air, and this is the primary reason why employing air agitation in an alkaline plating bath is rarely, if ever, recommended.
So, your plating bath has high levels of carbonates in it—how can you remedy this? There are a few options.