Stainless steel electropolishing and citric passivation
Two treatments. Different surface results.
ACS provides stainless steel electropolishing to ASTM B912 and citric acid passivation to AMS 2700 and ASTM A967 in Erie, Pennsylvania. We process small stainless parts, fittings, valves and other components with specified finish and cleanliness requirements. Eligible small-part electropolishing jobs can be reviewed for 24-hour turnaround.
Alloy, specification revision, surface condition and required testing or documentation.
QUOTE INFORMATION
What to include in your inquiry
Required treatment
Specify electropolishing, citric passivation or both, together with the applicable standard and revision.
Alloy & condition
Identify the stainless grade, overall dimensions, starting surface condition and any welds or difficult-to-access features.
Finish & records
Provide the required finish, acceptance criteria and documentation. For expedited electropolishing, include quantity and the required completion time.
SPECIFICATIONS
Electropolishing and passivation specification matrix
Confirm the specification revision and acceptance requirements with your order
Treatment
Specification
Information to provide
Electropolishing
ASTM B912
Alloy, starting condition, critical dimensions, required finish and verification criteria.
Citric passivation
ASTM A967 / AMS 2700
Required treatment, specification revision, cleaning condition and acceptance tests.
Inspection records
Agreed project requirements
Report format, traceability and any required surface or corrosion verification.
Required tests and documentation are agreed before processing. Include high-humidity, copper-sulfate or other acceptance tests when your specification requires them so ACS can confirm the scope.
SURFACE FINISH
Understanding Ra and electropolishing results
State the finish in measurable terms
Ra is the arithmetic average roughness of a measured surface profile. Specify microinches or micrometres: 10 microinches is approximately 0.254 micrometres. Include measurement locations and the required evaluation method.
Starting finish and geometry matter
Electropolishing can reduce microscopic surface peaks, but it does not guarantee removal of deep machining marks, scratches or every burr. Final roughness depends on the incoming finish, alloy, geometry and process. Send the starting Ra and target Ra for review rather than assuming a universal reduction.
Protect critical fits
Electropolishing removes material. Identify threads, sealing faces and close tolerances, and provide any permitted removal allowance. Surface measurement and final acceptance requirements must be confirmed in the quote.
No. Electropolishing removes a thin surface layer and can smooth and brighten stainless steel. Citric passivation removes free iron without polishing away machining marks. Specify the required treatment and acceptance criteria.
When is 24-hour electropolishing available?
It is available on eligible jobs after ACS confirms the part, quantity, arrival time and processing requirements. Contact ACS before shipping. Return transport time is separate from the agreed processing turnaround.
