We are manufacturing aluminum alloy wheels and are facing problems on what powder coats to choose as 1) Base coat that can hide marks on aluminum surface; 2) Metallic coat; and 3) Clear top coat. These should pass the salt spray, adhesion, UV, weatherometer, etc., tests. N. A.
We discussed this process in this column before for this same product. There are some 50+ formulators of powder coatings in the USA, many of which have the products you need. A list of them is available from www.pfonline.com (Products Finishing magazine) or www.powdercoating.org (The Powder Coating Institute). I would start discussions with several of these companies to obtain the finish properties you need. However, you will need to be more specific with the actual numerical values of the performance tests you want to satisfy with your coated product (i.e. hours of salt spray, UV, and weatherometer, etc. tests).
Here are some hints to get you started. Low-temperature-cure, anti-outgassing hybrid or epoxy powders are often used for the primer on these wheel products. TGIC polyester metallic coatings are often used to provide the color. And lastly, polyester or acrylic clear coats are applied for the final coat. Good Luck.