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Hardcoat anodize polish finish

We contract out hard coat anodizing on our own designed T6061 heat treated to a T6 condition Aluminum hose couplings. We have received samples from a company in the Far East which have a nice polish finish to it. We asked them what the coating is that enables them to achieve the nice finish so that we can determine if the coating itself would have any long term negative deterioration effect on the hose we couple to. We were told that the polish was a result of a pretreat of phosphoric acid which created this polished finish. I do not believe the vendor because as you touch the coupling finger prints or light smudge marks are easily seen. It appears to me that there is some sort of petrochemical polish on it. Does anyone have any idea what is being used? We really like the look and have not received samples that look this nice from any other vendor, but we want to make sure that we are not introducing other potential problems. If you know what the finish is, how would it perform in a salt spray test?

Martin Seabolt
Metal Products Designer - Winchester, Virginia
2004

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The vendor is referring to a "bright dip" process which typically involves a heated phosphoric acid, and nitric acid bath that the parts go into prior to the anodizing bath. I would believe your vendor.

Marc Green
anodizer - Boise, Idaho
2004