Electroplating - Plant Tour pt.8

The wet lab is where all bath maintenance testing is accomplished. We conduct tests such as hull cell analysis, atomic absorption spectrophotometry (AAS), titration, and pH monitoring. Hull cell testing is used to monitor the degree of brightness that an electroplating bath has. As the bath ages, the brightener chemistry is depleted and various organic byproducts of the plating reaction accumulate. This conditions leads to a steady decrease in the brightness of the electrodeposit. Rather than wait for the inspectors to decide that parts are no longer bright, we regularly test each bath for change. The hull cell test data is used to determine the appropriate amount of filtration and replenishment required for maintaining optimum brightness.

The AAS test is how we look for the presence and concentration of metals in a bath. Given that we electroplate a variety of different metals, we need to be on-guard for cross contamination of one bath by another. The AAS test is how this checking is done. Like most other potential problems, cross-contamination will appear at some time as a deterioration in the visual appearance or mechanical performance of the electrodeposit. By then, however, time and customer product is lost. We routinely monitor all baths for cross-contamination so that we catch and repair these situations before, not after, time and product is lost.