Posted: 20 April 2005 at 10:22pm | IP Logged

A. In electroplating, a negatively charged layer is formed around the part as the process continues. When using a direct current supply, this layer charges to a defined thickness and stays constant. This obstructs the ions from reaching the part. In pulse plating, the output is periodically turned off to cause this layer to discharge some. This allows easier passage of the ions through the layer and onto the part.

B. During the electroplating process, high current density areas in the bath become more depleted of ions than low current density areas. During the off period, ions have a chance to migrate to the depleted areas in the bath. When the on time for the pulse occurs, more evenly distributed ions are available for deposition onto the part. There are also many types of agitation that can help replenish ions in the bath along with the on/off pulsing.