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Anodizing parameters to get 50 micron thickness

I want to know for a coating of 50 micron (anodizing Al), what will be the parameters (temp, concentration and current etc.) using sulfuric acid.(also wm80 may be used)

How much maximum thickness (micron) of anodic coating can be given to an aluminium section when it is dipped in the bath containing sulfuric acid .wm80 is used in the bath.

I am working as a chemist in an anodising plant ( for aluminium) in Calcutta, India. Our plant plant output is 250sqm per day. We use sulfuric acid , wm80 (a brand from italtechno, used to restrict the dissolution of the formed oxide layer and thus allow us to work at 25-30 °C). Our customer wants a coating of 50 micron.please let me know the parameters required to achieve this. We are using the conventional rectifier. I will be grateful if you let me know more about this.

Thanks,

Abhijit Datta
- Calcutta, Westbengal, India

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50 microns is .00195" Your customer most probably wants hardcoat anodize to that thickness. The formula you use to figure out how to get that thickness is the 720 rule: 720 divided by the number of amps per ft sq you run at times the thickness you require = time to run ie 720 div by 36 amps per ft sq = 20 minutes x 2 = 40 minutes total

David A. Kraft
- Long Island City, New York

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Dave is right on the money with the 720 rule and 30-40 amps per sq ft. I don't agree with temp of 70f+ for hard coat. I am of the 30-32f school if you want real hard hard coat. Bath should be 180-200 grams per liter. Up to 225 for 2000 series.This info should be available from your supplier. Any more info and I'll have to send them a bill.

Drew Nosti, CEF
Anodize USA

Ladson, South Carolina