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Al hard coat anodizing and alcohol resistance

We are re-designing a product that will interact directly with medical devices (from stints to actual pharmeceutical products) and is subject to a lot of alcohol for lubrication and cleaning. We currently manufacture everything out of 304 SS (untreated) and would like to go to a 6000 series Al with a surface treatment combination of normal anodizing for the support structure and hard coating for the major contact & wear surfaces. There is no welding in the fab/manufacturing process on this assembly.

A customer has expressed some doubt as to the ability for the anodizing and hard coat to hold up to pure denatured alcohol or DI water. I have looked and looked and nothing seems to state definitively whether this combination is inert. Everything I have found makes me think that there will be no problem, but no direct. Any confirmation would be great.

Seth Adams
Mech Eng. - Pittsburgh, Pennsylvania, USA
2007

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You should have no problems with those 2 solutions on an anodized surface. Be sure to specify to seal the coating to your anodizing vendor, as this will improve corrosion resistance. Typically, hard coat is not sealed unless specified.

Marc Green
anodizer - Boise, Idaho
2007