What Is “Burning” from a Plating Bath?

We've all seen it. That crispy, flaky, nodular, usually dark deposit on the high current density extremes (edges, etc.). Usually, turning down the current is the reaction done immediately to try and remedy the problem. But exactly why does burning occur? An understanding of the mechanisms involved with the formation of a burn can better help a plater to avoid this nasty problem. Going back to high school chemistry (if you can remember that far back), you may have seen demonstrated the two electrodes from a battery, generator, or rectifier placed in a beaker of water. You will see gassing at … [Read more...]