The cycle time required to electropolish a part is primarily based on the current / amps and surface area of the part or total surface area and rectifer current if multiple parts are desired to be electropolished at the same time.

Visit the Electropolishing Current Required Calculation Spreadsheet to calculate the approximate cycle time required for a part or total parts for electropolishing

What is electropolishing? How does electropolishing work? contains more in depth information on electropolishing.

As a non-electrolytic process, passivation uses solutions like citric and nitric acids instead of an electrical current used in electropolishing to create a inert oxide layer / film and remove free iron and foreign matter from metal surfaces. Electropolishing, a non-mechanical interactive process, can be used on objects with complex geometries.  The electropolishing  process uses a combination of electrolytic chemicals and an electrical current to carefully eliminate imperfections and contaminants of metal part surfaces. This particular process is an alternative to abrasive fine polishing.  Electropolishing can be used to polish, deburr, and smooth metal components whereby doing so also causes material removal to occur including the free irons on the surface of the part. Electropolishing would be the more appropriate approach when  aesthetics are necessary.  A smoother, polished surface can result from electropolishing. Passivation, on the other hand, does not change or brighten the surface appearance and is not an effective method for removing surfaces that has been welded with oxide heat effect scale or heat treated.

Electropolishing  is an electrochemical process that removes material from a metallic part, typically stainless steel or similar alloys.  The part is immersed in a temperature controlled bath of electrolyte (typically mixtures of sulfuric acid and phosphoric acid) and the part serves as the anode as it is connected to the positive terminal of a DC power rectifier DC and the negative terminal of the rectifier is attached to the cathode which is typically made from titanium or other alloys which do not dissolve during the electropolishing process.

Visit What is electropolishing? How does electropolishing work? for more detailed information on electropolishing