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Want to strip trivalent chromate but not the zinc plating

as we have non-cyanide zinc bath the plated component is dipped in trivalent passivation and the same job got rejected due to some reasons I want to remove passivatio only without affecting the plating tell me is there is any way.

Jacf Peter
manager - India
January 15, 2009

You can remove it by caustic soda ⇦liquid caustic soda in bulk on Amazon [affil link]

Hatem Shaker
- Cairo, Egypt
January 21, 2009

You have to be very careful using caustic as it will also remove the zinc if left in too long or if the caustic is too strong. Consider using a 1 pound per gal of bicarbonate of soda at about 100F and then add tiny amounts of caustic soda ⇦liquid caustic soda in bulk on Amazon [affil link] to increase the rat of reaction as required.

Also, You can wet blast the chromate off. We had a wet blast cabinet and added a handful of 600 grit aluminum oxide and a couple of ml of liquid soap and it worked extremely well.

James Watts
- Navarre, Florida
January 23, 2009

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