There are a number of process parameters critical in an electropolishing procedure that must be controlled to produce a quality surface. These parameters are identified as “essential variables” and a change in any essential variable affects the outcome of the process. The essential variables are:
•Amperage/time as defined in ampere-minutes per square inch - This determines metal removal, allows for removal calculation, and establishes a repeatable process on a variety of part shapes and sizes.
• The temperature range of the bath during operation - This Variable affects distribution which in turn controls uniformity of surface metal removal. Good practice includes maintaining the bath temperature within a specific range, for example +/- 10 degrees (+/- 5 degrees C).
• Bath monitoring - The electrolyte must be maintained to a controlled composition, Factors of greatest concern are metal pick up and the water content, both of which if not controlled can affect EP quality. During use, metal salts increase in the electrolyte and are controlled by decanting and adding new electrolyte. Also the electrolyte is hygroscopic and takes on water or loses water depending up on the operating operating environment. The water content can be controlled by increasing bath temperature to “cooking off” excess water or by adding water as required.
• Requiring an EP procedure specification with proper control of essential variables is a major step in assuring quality electropolishing workmanship.
• Ultraclean Electropolish, Inc. utilizes over 30 years experience
