Using Alconox passivation solution to protect stainless steel parts from corrosion
Passivation is the process of forming a passive layer of chromium oxide on the surface of stainless steel to protect it from corrosion. This is done by adding a chemical that removes free iron and allows chromium oxide to form. The reference for passivation of stainless steel is ASTM A967. See the Critical Cleaning Procedures section of this guide for passivation tests.
CITRANOX and CITRAJET for passivation applications—safety, efficacy and ease of use
- May be used at a 30% concentration in water at a temperature of 140 degrees F for 20–30 minutes
- Exact conditions will vary depending upon the type of stainless steel and surface finishing
- Recommended for manual soaking or soaking in an ultrasonic tank
- If applied by a spray system where there is agitation of the air, CITRAJET should be used at the same conditions listed for CITRANOX
- Much safer and effective than using nitric acid formulations for passivation