Passivation removes surface impurities that cause corrosion and promote friction-related damage in stainless steel. When applied by skilled professionals, the result is a protective film that won’t create a variation in component tolerances.
Passivation removes the surface contamination created when stainless steel is machined and fabricated. These contaminants can result in premature corrosion that could ultimately damage the component. In addition to surface cleaning, passivation forms a thin, transparent oxide coating that fights selective oxidation.
We specialize in:
How Is Passivation Performed?
Passivation is accomplished in two fundamental steps:
- A thorough cleaning cycle removes oils, greases, forming compounds, lubricants, coolants, cutting fluids and other undesirable organic and metallic residue. General degreasing and cleaning can be accomplished in many ways, including vapor degreasing, solvent cleaning and alkaline soaking
- A nitric acid bath in the 20 to 50% range by volume, with typical immersion times between 20 min and two hours. Bath temperatures range between room temperature and 160°F.
Factors in Effective Passivation
Careful process control is essential for the application of a quality passivation coating. A failure in process control can mean extreme pitting, etching, or even catastrophic failure and total dissolution of the entire component. A range of variables are factored into the calculations:
- Bath control (time, temperature and concentration)
- Water purity
- Adjustment of bath solution to the stainless steel type
- Chemical maintenance through the passivation process