Nitric Passivation Service
Though citric passivation is gaining popularity because it’s more environmentally friendly, nitric acid passivation is still the more popular form of passivation because of its ability to form a chromium-rich oxide passive layer on stainless steel. Able has provided passivation services since 1954.
Before using nitric acid passivation, we ensure that all steel surfaces must be free of oxide scale, organic contamination, machining lubricants, oil, and grease.
The Need for Passivation
As explained in Euro Inox’s publication Pickling and Passivating Stainless Steel, “Steel delivered from manufacturing mills and reputable stockholders will be fully passive. The treatment may be needed however on intricately shaped machine parts. In these special cases, the supply of oxygen to all the newly formed surfaces may be restricted, resulting in the natural passivation process taking longer to complete, than on the open, exposed surfaces. There is a danger that if parts like these are put straight into service in an environment normally considered suitable for the particular steel grade used, they might not be fully passive and suffer unpredictable corrosion. Passivation treatments done under these circumstances eliminate these unnecessary corrosion risks.”
Passivation vs. Electropolishing
After nitric passivation, do your parts still have issues with burrs, micro cracks, contamination, corrosion, or cleanability?
Do you want to treat metals beyond stainless steel, like Nitinol or titanium?
If so, electropolishing is likely a better option. Among other advantages, electropolishing provides the ability to remove a microscopically precise layer of surface material, to tolerances as low as +/-.0001″, depending on the alloy. This degree of precision and consistency, along with the ability to remove a variety of surface imperfections in one process, is why electropolishing is so often specified for critical parts used in medical implants and surgical instruments, aerospace components and fragile or critical parts used in other industries. It’s a one-stop process for a micro-smooth, ultraclean, corrosion and pathogen-resistant surface finish – with 30 times more corrosion resistance than passivation.
Electropolishing eliminates the need for additional metal finishing processes like hand deburring, tumbling, cleaning, and passivation.
Whether electropolishing or passivation is the right process for you, we offer the highest-quality finishing services. Our state-of-the-art 45,000 SQFT facility operates 3 shifts, 5 days a week. We offer expedited service, can handle parts of any size, and provide customized processing for every part, including custom racking. Start with a sample finish of your part for free.
Contact us to learn more about nitric passivation