Please take full advantage of our information and contact us with any questions or needs that you may have. At KEPCO we have dedicated ourselves to be your resource for information regarding electropolishing, passivation, and stainless steel finishing.
What is Electropolishing
Electropolishing is an anodic dissolution process in which the metallic anode surface is smoothed and brightened under optimum conditions of current density and temperature.
Electropolishing is used as a replacement for mechanical finishing, polishing, buffing and mass finishing. In addition to making a part’s surface smoother, it is a more visible means of brightening, deburring, passivating, stress relieving and otherwise improving the physical characteristics of most metals and alloys.
Basic Principle of Electropolishing
Electropolishing is a process by which metal is removed from a work piece by passage of electric current while the work is submerged in a specially-designed solution. The process is essentially the reverse of electroplating.
Electropolishing Process Requirements
Electropolishing is accomplished in a series of wet processing steps using specially designed tanks, similar to electroplating or anodizing.
Benefits of Electropolishing
Electropolishing produces a number of favorable changes in a metal part which are viewed as benefits to the buyer. All of these attributes translate advantages depending upon the end-use of the product.
Electropolishing by Induction
The inductive method of electropolishing is useful in finishing certain types of surfaces which require polishing on only one side.
General Process for Electropolishing
The general process incorporates the principles of Good Metal Finishing Practice, and is designed to produce consistent, top quality finishes in day-to-day production.
Cleaning Prior to Electropolishing
To avoid pitting, surface etching, non-uniform finish, carbon residues in AES profiles.
Cleaning for Electropolishing
Oily, greasy, or waxy residues on the surface of the work create a barrier to direct contact between the electrolyte and the metal being electropolished.
Racking for Electropolishing
The current density around any given part varies with the part geometry, and is seldom uniformly distributed.
After alkaline cleaning, it may be necessary to treat the parts in an acid bath to accomplish one or more of the following objectives.
Neutralization of Cleaner
The preferred choices of chemicals for neutralization of alkaline drag-in include those acids and acid salts which are components of the electropolishing bath.
Surface Roughness Measurements
In the United States, the “Ra“, or roughness average, is the most commonly used parameter for expressing measurements of surface contour.
Passivating Stainless Steel Parts
A crucial step in maximizing the corrosion resistance of stainless steel workpiecs, passivation forms an extremely thing, protective oxide surface film.
Acid Baths for Deoxidizing/Descaling
Muriatic acid is probably the most common bath use for rust removal in metal finishing operations.
Acid Dips for Neutralization
Soak cleaning nearly always leaves a film of alkaline material on the surface of parts.
A significant problem in electropolishing involves removal of weld scale prior to electropolishing.
Descaling of Deoxidizing
Acid descaling refers to the use of an acid bath to remove weld discoloration, heat treat residues, rust or other surface oxides.
The Effect of Electropolishing on SS Welds and Heat Affected Zones
Electropolishing Stainless Steel Implants
Selecting Stainless Steels for Bio-Pharmaceutical Service
Optimization of Cleanability
Pitting Corrosion of Metals
Thermal Mass Flow Controller Material and Surface Finish Enhancement
Type 316L-SQC Stainless Technical Report
How Production Technologies Influence Surface Quality of Ultra Clean Gas Supply Equipment: Requirements for Surface Quality
How Production Technologies Influence Surface Quality of Ultra Clean Gas Supply Equipment: Assessment of Surface Technologies
How Production Technologies Influence Surface Quality of Ultra Clean Gas Supply Equipment: Inspection Methods for Surface Evaluation
How Production Technologies Influence Surface Quality of Ultra Clean Gas Supply Equipment: Material and Construction
Selected Electropolishing Literature