QMS Registered to ISO 9001:2000

Pro-Fab's standard "2B" electropolished finish:

Electropolishing and passivation services:

Pro-Fab is proud of our 10 years of quality electropolishing services located in Bosque Farms, New Mexico 15 miles south of Albuquerque. Pro-Fab's 1,500 square foot electropolishing facility includes, double containment of hazardous materials, our largest  electropolish tank measures  4 foot wide 8 foot long and 4 foot deep.

What is electropolishing?

Electropolishing is an electrochemical process by which metal is removed, unlike electroplating, which adds metal. The resulting stainless steel surface is microscopically featureless, bright, clean and smooth.

Electropolished products, who uses them?

    Electropolished products are used by Semiconductor, Aerospace, Chemical processing, Pharmaceutical, and Food processing industries are among just some of the industries that require ultra clean stainless steel products. Sometimes electropolishing is used only for aesthetic results and not just for ultra clean surfaces.

How does electropolishing stainless steel work?

    The electropolish (EP) process is used to promote corrosion protection and deoxidize metals, predominantly stainless steel. Pro-fab electropolishes 304 and 316L stainless steel to a standard 2B finish although the finish of the metal prior to electropolishing governs the end results.  A heated electropolishing tank is used in conjunction with a Direct Current electrical charge. The part (anode) to be polished has a positive charge while the tank or rack is negatively charged (cathode). When the current is applied electrons flow from positive to negative and removal of metal takes place. The anodic layer is formed. Metal ions diffuse through this layer deoxidizing stainless steel by removing iron at a faster rate than other metals. The end result is a "chromium-oxide" layer that does not emit particles. After the electropolishing tank, the part is dipped in a nitric acid tank (passivated). The stainless steel part is then rinsed in a hot DI (de-ionized) water tank.

Terms:

Stainless Steel Part (Anode): The part that is being electropolished. This piece of stainless is connected to the positive side of the electrical rectifier and functions as a sacrificial anode in the process. 

Electropolishing Tank: A mixture of phosphoric and sulfuric acids into which the part is placed for processing. This bath is the ionic solution which wets the part and allows an ionic transfer from anode (positive) to cathode (negative). 

Rack (Cathode, usually copper): The "Rack" that is connected to the negative end of the rectifier and receives the metal ions from the stainless steel part. The cathode is made out of metal and is shaped in such a way as to provide an even current to the surface of the work piece. 

Anode Layer (Drag Out): The thick viscous film of electropolishing solution that forms on the surface of the part during the process of electropolishing.

Nitric Acid Tank (Passivation): This removes the anodic layer.

Hot Rinse (DI Water): This hot de-ionized water bath removes the nitric acid.

Copyright © 2003 Pro-Fab, Inc
Last modified: 06/15/07