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What is Passivation?

Passivation is a term for a variety of processes that make a metal or other substance unreactive, or passive, by altering the surface layer or coating the surface with a thin inert layer. Because ferrous metals flake when oxidized (e.g. rusts), anodizing is not an appropriate protection technique.

As a result, passivation is most commonly used for ferrous parts, especially stainless steel. For ferrous metals passivation removes free iron molecules embedded in the surface of the part and leaves a protective coating which protects the underlying material. 


Properties and Benefits

  • Prevents rust formation on ferrous parts, including stainless steel
  • Prepares surface for other finishes, including priming and painting
  • Reduces / prevents reactivity to other parts
Specs & Certifications
  • QQ-P-35 --- NADCAP Approved, ROHS Compliant
  • AMS-QQ-P-35 --- NADCAP Approved, ROHS Compliant
  • FED-QQ-P-35 --- NADCAP Approved, ROHS Compliant
  • AMS-2700 --- NADCAP Approved, ROHS Compliant
  • ASTM A380 --- NADCAP Approved, ROHS Compliant
  • ASTM A967 --- NADCAP Approved, ROHS Compliant
  • ASTM B912 (Electropolish & Passivate) --- ROHS Compliant
  • ASTM F8 --- ROHS Compliant
  • MIL-C-13924 (Black Oxide Coating)
  • MIL-DTL-13924 (Black Oxide Coating)
  • More specs available - Contact us!
Applications / Industries
  • Aerospace
  • Architectural, including Marine Architecture
  • Food Preparation, Processing and Handling
  • Medical
  • Military

Unique Substrates

In addition to our Passivation services, AOTCO plates and anodizes many exotic and uncommon Substrates that most plating providers won’t or can’t do. Please click to see a list of the Substrates we commonly plate.

Contact Us

If you’ve got a question about plating or other surface finishing, please reach out and speak with our experts to see how AOTCO can best help you.

If you need a finishing partner who will listen carefully and then Make it Happen for You, call AOTCO at 1 888 275 0880

Since 1975 AOTCO Metal Finishing LLC has delivered outstanding results for clients with the toughest requirements for metal finishing.

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