What is Electropolishing?

Electropolishing is an electrochemical process similar to, but the reverse of, electroplating. The electropolishing process smooths and streamlines the microscopic surface of a metal object such as 304, 316, and the 400 series stainless steel. As a result, the surface of the metal is microscopically featureless, with not even the smallest speck of a torn surface remaining.



In electropolishing, the metal is removed ion by ion from the surface of the metal object being polished. Electrochemistry and the fundamental principles of electrolysis (Faraday's Law) replace traditional mechanical finishing techniques, including grinding, milling, blasting and buffing as the final finish. In basic terms, the metal object to be electropolished is immersed in an electrolyte and subjected to a direct electrical current. The object is maintained anodic, with the cathodic connection being made to a nearby metal conductor.

During electropolishing, the polarized surface film is subjected to the combined effects of gassing (oxygen), which occurs with electrochemical metal removal, saturation of the surface with dissolved metal and the agitation and temperature of the electrolyte.

Hydrogen embrittlement does not occur in the metal because the surface is exposed to oxygen. In fact, electro polishing is dehydrogenated the piece surface like heating and cooling process without fatiguing.

Another advantage is that the bacteria cannot multiply as well on the surface devoid of hydrogen. This make electro polishing the appropriate choice for medical, pharmaceutical, semiconductor and food industries.

The combination of the two properties of absence of the directional mechanical polishing lines and hydrogen free surface, create a hygienic surface where no bacteria or infection can result in proliferation or accumulation.

Benefits of Electropolishing:

>Better Physical Appearance

>Enhanced Mechanical Properties

>Better Corrosion Protection

>Ease of Cleaning

>Disinfect surfaces are easier

>Catalytic reactions on surfaces is prevented

>Good reflection of light on the surface of parts

>Creating hygienic surfaces

>Carbon removal of metals

Electropolishing Standards:

>ASME BPE Standards for Electropolishing Bioprocessing Equipment

> SEMI F19, Electropolishing Specifications for Semiconductor Applications

> ASTM B 912, Passivation of Stainless Steels Using Electropolishing

> SEMI F17 - For high purity quality electropolished 316L Stainless Steel tubing, component tube stubs and fittings made from tubing.

> SEMI F19 - For wetted surface finishes of electropolished 316L stainless steel components.