The authoritative public forum
  for Metal Finishing since 1989
-----

Will a clear anodized finish hold up in either / both chromatic and sulfuric acids?

I am a mechanical engineer with a fluid products company and am looking for some insight on aluminum finishing. My current applications involves a rolling platform for workers to stand on that will come in contact with both chromatic and sulfuric acids. The platform is to be made from structural aluminum extrusion that comes standard with a clear anodized finish (AA M10, C22, A31, Clear). I am wondering if this finish on aluminum extrusion will hold up in the environment described above? If not, is there some alternative finish that I should consider? Any insight is greatly appreciated.

Thank you.

David Humphrey
Mechanical Engineer - Stillwater, Minnesota, USA
2004

First of two simultaneous responses --

I do not believe an anodized coating is the best application for the scenario you described. I guess I would suggest powder coating with an Epoxy resin base and maybe even have a Zinc rich primer applied prior to the Epoxy powder. As long as these parts will not be exposed to UV light this might work well. I have powder coated parts that have exceeded Whirlpool specs using Epoxy based powders. I am sure their are better suited finishes that I am not aware of but for the industry I serve this would be my suggestion.

Bruce Pfaff
- Wausau, WI
2004

---

Second of two simultaneous responses --

I doubt it would hold up. If it were me, I would have them powder coated with some type of fluoropolymer.

Marc Green
anodizer - Boise, Idaho
2004