Aluminum Anodizing Electropolishing Passivation
MEDCOAT 2000
Quality Assurance
Process Validations
Ti-Med Ti-Med 2
Passivation
       
Passivation - Improving Corrosion Resistance
 

Passivation improves the corrosion resistance properties of components made of precipitation-hardened, austenitic, ferritic and martensitic steels. Passivation treatments improve the surface condition of stainless steel by dissolving iron that has been imbedded in the surface during forming or machining. If allowed to remain, the iron can corrode and give the appearance of rust spots on the stainless steel.

Passivation, which consists of immersing stainless steel components in a solution of nitric or citric acid without oxidizing salts, will dissolve the imbedded iron and restore the original corrosion-resistant surface by forming a thin, transparent oxide film.

Passivation - Corrosion Resistance

 
Features

Specifications

• Maximum stainless steel corrosion protection without plating.
• Superior clean surface.
• Eliminates iron contamination reactions with
  other materials.
• No rust discoloration.
• Surface prepared for priming and painting.

               AMS-QQ-P-35 (Replaced QQ-P-35)
               AMS 2700
               ASTM A-380
               ASTM A-967
               ASTM B-254
               ASTM F-86 (Titanium Components)
               MIL-S-5002

       
Testing

Water Immersion
Registered to ISO 9001:2008
Verifies the passivation process on all grades of stainless steel, with exception of 440C. After testing, specimens shall show no signs of rust or corrosion.
     
Copper Sulfate
Verifies the passivation of austenitic stainless steel in the 200 and 300 series conducted in accordance with MIL-STD-753 Method 102. The specimens shall show no signs of copper deposit.
     
Salt Spray
Performed in accordance with ASTM B117 for 2 hours, when specified by engineering drawings. After testing, specimens shall show no signs of rust, stain or corrosion.
     
Applications
 
The Electrolizing Corporation of Ohio passivation process meets ASTM A-967-01 and AMS-QQ-P-35, Types 2, 6, 7 and 8. We take care in passivating austenitic or low chromium grades of stainless steel. We do not recommend passivating stainless steel that has a carbonized/nitrided surface, because nitric acid will dissolve the surface and reduce the size of the component. It is important that you identify the type of stainless steel to be passivated.