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Electropolishing is an electrochemical finishing process that removes a thin, uniform layer of surface metal by anodic dissolution. It smooths microscopic peaks, removes free iron and contaminants, and improves surface finish, cleanability, and corrosion resistance on stainless steel and other alloys.

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Passivation is a chemical treatment that removes free iron from stainless steel and strengthens its protective chromium-oxide layer, restoring corrosion resistance without changing part dimensions.

Oxygen cleaning removes oils, greases, hydrocarbons, and particulates from components used in oxygen-enriched environments, reducing the risk of fire or explosion and meeting standards such as ASTM G93 and CGA G-4.1.

Mechanical polishing smooths a metal surface using abrasives applied in progressively finer steps. It removes deeper imperfections and welds and is often used to prepare a surface before electropolishing.

Pickling is a chemical process that removes scale, weld oxides, and heavy contamination from stainless steel fabrications, usually as preparation before passivation.

Electropolishing removes a measurable layer of metal to smooth and brighten the surface and improve corrosion resistance. Passivation removes only free iron and restores the passive layer without changing the finish. They are often performed together.

Pickling removes scale and weld oxides and alters the surface; passivation removes free iron and restores corrosion resistance without changing the finish. Heavily contaminated or welded parts often need pickling first, then passivation.

Mechanical polishing uses abrasives to physically smooth a surface; electropolishing uses an electrochemical reaction to dissolve surface metal. Electropolishing also improves near-surface chemistry and corrosion resistance, and the two are frequently combined.

ASME BPE (Bioprocessing Equipment) is the standard for the design, materials, and surface finish of pharmaceutical and biopharmaceutical equipment, where hygienic, cleanable, low-roughness surfaces are required.

ASTM A967 is the standard specification for chemical passivation treatments for stainless steel parts, defining acceptable nitric- and citric-acid passivation methods and testing.

ASTM B912 is the standard specification for passivation of stainless steel using electropolishing—recognizing electropolishing as an accepted method of achieving a passive surface.

Stainless steel, nickel alloys, Hastelloy, AL6XN, and titanium are commonly electropolished. Suitability depends on alloy composition, part geometry, and finish requirements.

Rouge is an iron-oxide discoloration that forms on stainless steel surfaces, common in high-purity and high-temperature water systems. Electropolishing and passivation help remove rouge and reduce its recurrence.

Yes. By removing free iron and embedded contaminants and promoting a chromium-rich passive layer, electropolishing measurably improves the corrosion resistance of stainless steel and similar alloys.

Yes. Harrison provides on-site electropolishing, passivation, and related services for components that are too large or impractical to transport, with crews experienced in field execution.