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What alternatives are available for Chromate Coatings?

We have been instructed to stop using Chromate Conversion Coatings due to the environmental concerns of Hexavalent Chromium. We have been using Clear & Yellow Chromate Coatings on Aluminum parts for electrical conductivity. What alternatives do we have to replace this finish?

Samusel Ferguson
- Newark, DE, USA
2005

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First of two simultaneous responses --

I gave a paper at SurFin 2004. "Conversion coatings for Aluminum and Magnesium". It includes non-chrome processes. The paper is available from AESF [www.nasf.org].

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])
2005

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Second of two simultaneous responses --

Sam

You do have an alternative that gives you everything except the yellow color. The new products are based on trivalent chrome and meet or exceed the requirements of MIL-C-5541 and the conductivity test. This material has been in the works for a while now but until the pressure was put on by political and environmental groups changing wasn't eminent. Now things are really moving!

Drew Nosti, CEF
Anodize USA

Ladson, South Carolina

2005