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Salt Spray Life of powder coat vs zinc olive green passivation

I would like to know the difference (hours) of salt spray test life between a] powder coated ( 50 microns Thickness ) b] Zinc plated with Olive Green passivated (8 microns thickness) steel sheet ?

Ravi Bakshi
- Mumbai, Maharashtra, India
2003

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The industry average for powder coating is > 350 hours to Red rust for powder coating. Olive chromating should get you past >150 hours to white rust and > 300 hours to red rust if your minimum thickness is 8 microns.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2003

I am getting my components powder coated with light grey, Dark grey and structure finish. Thickness is 80 microns. How many hrs of salt spray test it should pass?

Raghavendra Prasad
- Ahmedabad, India
April 27, 2011

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Hi, Raghavendra.

Khozem has already offered a generic answer which is probably as good as you are going to get because the answer is going to depend on the type of parts, the type of powder, the care applied in pretreatment, etc. The supplier should be able to give you estimates for the particular powder you are using; usually this would be based on the type of polymer used, rather than its color. What is the pretreatment sequence?

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 27, 2011