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-----Determining what finishing process was used on an aluminum part
Dear Sir or Madam,
I have a deep drawn aluminum urn that has a bright shiny outside surface. I would like to know if there is any way to find out how this surface finish was achieved. e.g. if it was anodized is there some way to verify that?
Leo Driessen
- Melbourne, Australia
Hello Leo!
An anodized aluminum surface is non-conductive. Perhaps you can check it with a voltmeter.
Good luck!
Lee Gearhart
metallurgist - E. Aurora, New York
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If it is not oxidizing into white spots it's either because it is anodized or because it has a clear lacquer on it. The lacquer would be relatively soft while anodizing is very hard. I guess I might try to scratch a non visible area and immediately test it with an ohmmeter. If it doesn't conduct after the attempted scratching, it's probably anodized. If it does, it was probably lacquer coated. A lab could give you a definitive answer instead of a "probably".
Ted Mooney, P.E.
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