Passivation of Corrosion Resistant Metals



Passivation is the process of removing iron and iron compounds from the surface of stainless steel alloys. These iron contaminants are invisible to the naked eye and can result from improper cleaning or storage. Contamination can also occur on the surface of the metal as a result of grinding, machining and other manufacturing operations. Sulfur, which is added to some alloys for increased machineability, can also increase the chances of corrosion to occur on stainless steel. Passivation will also remove any sulfide contamination that may be present.

Passivated Cylinder
The most common passivating solutions use nitric acid to dissolve the contamination from the surface of the stainless steel. Although nitric acid is the common denominator in most passivation solutions, different formulations are required for different alloys (300 series, 400 series, P.H. Alloys, etc.) of stainless steel. These formulations have been developed in order to achieve the best cleaning of the contaminants while avoiding any removal of the stock alloy.

It should be noted that passivation does not remove heat staining due to grinding, welding or heat treating. Heat stains and certain other types of soils should be removed by acid cleaning (pickling) the stainless steel prior to the passivation process. Our technical representative can assist you in determining how to obtain the best results from stainless steel passivation of your parts.



Ampere Metal Finishing Facilities



Ampere Metal Finishing has the capacity to handle a variety of shapes and sized parts. Our passivation processes comply with automotive, aerospace, and military specifications.

We are able to process parts by rack, barrel or baskets, which allows us to choose the most efficient and appropriate method for your production needs no matter how large or small.

Our Passivation processing tanks are 24" x 23" x 32" deep, with a one ton lifting capacity.

We have developed a special process where we can also passivate oversized parts as well.


On-Site Service Available!

For those fixtures and equipment that are either too large to move or scheduling demands prohibit disassembly of the unit to ship to us for passivation, we offer on-site service. Our mobile passivation equipment can come to your premises in order to save you down time. We can adapt our process to be suitable for the configuration of your components and schedule the treatment to accommodate your needs.

Contact us today for a free estimate for on-site services.



Passivation Specifications



Ampere Metal Finishing certifies our Passivation to many specifications. The following lists some of the more common specifications for Passivation. If the particular specification you require is not listed, please contact us for further information.

For a complete list of all the specifications available click here.

Passivation Specifications
  • AMS-QQP-35, TYPE II
  • AMS-QQP-35, TYPE VI
  • AMS-QQP-35, TYPE VII
  • AMS-QQP-35, TYPE VIII
  • ASTM A380
  • ASTM A967
  • DSS-88001
  • F-16
  • MIL-F-14072 E-300
  • MIL-S-5002
  • MIL-STD-171- PARA 5.4.1
  • MIL-STD-186E, NO. 216
  • NUP.0411 REV 1
  • NUP.0412 REV 1




The technical information presented on this site is considered reliable to the best of our knowledge. However, this information is presented as a convenience to our visitors. Ampere Metal Finishing Ltd. does not warrant the accuracy or completeness of the Information contained on this server. We urge that our customers perform their own testing to confirm suitability of the product prior to committing to full production. THE INFORMATION IS PRESENTED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. To view our Conditions of Sales and Warranties click here.