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Iron Phosphating instead of Vapour Degreasing?

We are having a number of Zintec (Zinc electro-coated steel) sheet metal parts made by a contract manufacturer and we require them cleaned/degreased before delivery. The most common method I know of (and have asked for) is Vapour Degreasing. However, the contract manufacturer does not have the facilities to do this but has recommended an Iron Phosphate pre-treatment (spray not immersion). I am aware that this is the most common pre-treatment for painting, but I'm cautious about its suitability for cleaning/degreasing.

Can anyone tell me the affects of the Iron Phosphate conversion coating on the Zintec, in particular its cosmetic appearance and electrical conductivity?

Our parts make up a personal computer enclosure for use indoors and they will have no other treatment after the proposed Iron Phosphating.

Thank you,

Tim Douglas
- St. Albans, Hertfordhsire, England
2005

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2005

Tim,

Iron phosphate will not have any effect on the zintec surfaces. Probably your subcontractor has a pretreatment plant (spray) where the iron-phosphate solution is used for as well degreasing as for phosphating. This works on steel, but not on zinc. You (your subcontractor) can however use this system for degreasing your parts without any problem. There will be no residue left on the surface. Also the electrical conductivity will not be affected.

Remmelt Bosklopper
- Enschede, The Netherlands