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How to pass 720h salt spray test for a zinc plated cabinet

I have not idea how the thickness will be for a zinc plated cabinet for passing a 720hr salt spray test.
Does it needs special plating?

Ken Yang
plating shop - Tainan, Taiwan
June 10, 2009

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June 14, 2009

Dear Ken,
Zinc gives very little protection (10 hours to neutral salt spray). The thickness will not improve this much.
You will have to look at very good thick-layer passivation and sealer to be able to achieve such high hours. Most probably you will have to go to alloy plating like zinc nickel.
Best regards

Trudy Kastner
electroplating service - Durban, KZN, South Africa

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July 13, 2009

Dear Ken,

first let us know are you looking 720 hours of White rust or Red rust.

I assume you are talking about red rust as 720 hours of white rust is very difficult and a rare case,yet possible with the usage of very good passivates and top coats.

Generally acid or alkaline zinc won't be able to give you so much of life. You can try Zinc nickel alloy plating or zinc iron alloy plating.

Or even there is technology called zinc flakes which can help you to achieve 1000 hours of red rust. Its a non electrolytic process where in you have to dip and bake the component in the over very similar to your top coat or sealers.

Hope this helps

All the best

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