Summary for zirconium passivation Discussion
Zirconium-based passivation is discussed as a chromium-free treatment that is known to work effectively on aluminum, but the thread does not establish the same level of effectiveness on carbon steel. In the later question, Joseph Califano asks whether zirconium can be visually detected on a coated substrate for a quick presence check. The answer says a visual test is not the practical route; instead, thickness can be analyzed by XRF, but only if the coating is thick enough—about 0.025 microns. For commercially used nano-zirconium coatings, which may be as thin as 0.0000025 microns, the answer notes that spectrum photo analyzers are used. Overall, the discussion points to analytical measurement rather than visual inspection for confirming zirconium coatings.
Q. How does a chromium free passivation like zirconium passivation work? I learned it is effective on Al. Is it also effective on C-steel?
Johan Thoelen
corrosion engineer – Heverlee, Vl. Brabant, Belgium
2004
Q. Does anyone know how to visually detect zirconium on a substrate. I am coating a substrate with a zirconium complex and I want a quick visual test to verify that zirconium is present.
Thank you
Joseph Califano
– Branchburg, New Jersey, USA
April 29, 2013
A. It is possible to analyze the thickness through XRF but only in the event the coating is as thick enough as 0.025 microns.
In the case of commercially used Nano Zirconium the thicknesses area as low as 0.0000025 microns and for this there are Spectrum Photo analyzers.
Khozem Vahaanwala
Saify Ind
Bengaluru, Karnataka, India
June 16, 2013