Delmet stainless steel excellence since 1949


The passivation of stainless steel is a process that happens spontaneously in nature, but it can be accelerated and perfected, following pickling, to allow the formation of an anticorrosive and contamination-free protective layer with the aid of specific chemical compounds.


After pickling, the steel is able to autonomously restore the protective chromium oxide film, but this self-passivation process takes a long time and requires particular conditions. Passivation is a process that induces the formation of this protective layer by means of solutions that are more oxidizing than atmospheric oxygen, such as nitric or citric acid or thanks to the action of an external anodic current as in the case of electropolishing (ASTM B912)

These two types of passivation are termed spontaneous and induced.

Pickling and passivation treatments can be performed in accordance with ASTM A480 and ASTM 967 standards by immersion or spray using gels or liquids, with products completely free of or containing nitric acid, according to the customer's specifications.

After treatment, it is possible to check the effectiveness of the treatment using our passivation test, which also allows you to detect any contamination.

Plants, Contract Services, and Chemical Products for Steel Care

Excellent Results and Professional Support!

For the care of your steel, rely on true experts. With Delmet, corrosion and other issues affecting the surface treatments of stainless steel are numbered days!

Would you like to receive more information or speak with one of our managers? Fill out the request form next to this text, and you will be contacted as soon as possible.


Do you need information? Fill out the form and we will respond as soon as possible.
   I have read and accept the privacy policy » Privacy policy *