Electropolishing FAQs

Electropolishing brightens, cleans and smooths the surface of components for both aesthetic and functional purposes. Below you’ll find GMF’s answers to some of our customers’ frequently asked questions about electropolishing.

What exactly is electropolishing?

Electropolishing is an electrochemical process used on stainless steel and other metal alloys to change the material characteristics of the surface layer of the component part. It’s often characterized as the opposite of electroplating: Rather than depositing a metallic layer through plating, in electropolishing you’re removing metal on a microscopic level from the surface of a part.

What are the benefits of stainless steel electropolishing?

The benefits of electropolishing are numerous and most often relate to the improvement of surface topography and corrosion protection.

During the electropolishing process, material is removed more readily on microscopic high points of the metal, resulting in a significantly smoother, brighter, and more reflective surface. It removes imbedded particles of elemental iron in the stainless steel, leaving a chrome-rich surface, which can naturally passivate and achieve dramatically enhanced corrosion resistance properties.

Electropolishing is also valuable for the purposes of deburring, controlling size, material de-stressing, removing EDM recast, and reducing surface friction.

How much material is removed during the electropolishing process?

Material removal is a factor of process time, temperature of chemistry, and amount of electrical current being applied to the work piece.

Standard processing will typically remove between .0003” and .0007” of material, but by manipulating the process parameters you can fine-tune the desired removal amounts. High-end removal for dimension tolerance typically does not exceed .003”.

Are there limitations to what electropolishing can do?

Yes. Electropolishing does not conceal, hide, or cover inclusions in the raw material. Heavy scratches, seams and material pits will remain as the electropolishing process removes high spots around those areas with limited ability to polish the recessed imperfections.

Impurities embedded in the stainless steel itself are also a concern that may sometimes be difficult to overcome.

Why work with PEP General Metal Finishing?

Because of our commitment to helping our customers. General Metal Finishing has been an industry leader in specification finishing for more than 40 years and we understand we’re judged on the product we deliver and the services we offer. Our ISO 9001 and ISO 13485 registrations, Nadcap accreditation, and numerous OEM processing approvals will hopefully give you a sense that we’re serious about what we do and how we do it.