Q. We plate a large volume of wire part for one of our customers and have noticed that the amount of pitting has increased dramatically in the last few months. The pits appear to be on one side of the wire. The customer recently told us that the supplier of the wire has recently changed. Is this the cause of the pitting?—J.S.
A. Very likely! What is probably happening is that impurities are embedded in the wire during the drawing process. These impurities show up as pits during the plating process. The drawing dies should be checked and a better grade of wire specified. You should also revisit your cleaning process prior to the plating step.