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Zinc trivalent with TOP SEAL to last 480 hrs SST life

Can anybody help by recommending the suitable top sealer that can enhance Zinc trivalent (white) coating to 480 hrs red rust life?

please don't recommend the alternate coatings like zinc nickel, Ze-Fe coatings etc as I look for the answer for the above question please.

Gnans Thiyagarajan
product designer - Seremban, Malaysia
April 3, 2009

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Hello,

Hrs to Red rust in 5% neutral ss test generally is proportional to zinc plating thickness,though sealant may help in delaying the appearance of white rust.Hence only by by increasing the plate thickness you may achieve the required hrs provided the quality of trivalent thick passivation and sealant combination is good enough to retard white rust at least for 120 to 150hrs.

S.Ramajayam

Subramanian Ramajayam
consultant - Bangalore, India
May 29, 2009

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July 13, 2009

Dear Friend,

Red rust is mostly dependent on the thickness. Alkaline zinc plating with give a better life than acid zinc even with lower thickness.

Using a good quality passivate and top coat will help.

Regards

S.V. Aurobind
plating process supplier - Bangalore, India

To get 480 hours of 5% red rust, you would need a thickness of 20 microns of zinc. Then use top of the line passivations and sealers or a technology that incorporates nano ceramics in the passivation.

A S Kulkarni
- Nasik, INDIA
July 31, 2009