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Seeks literature on aluminum reflector surface gloss

1995

I am at present starting a literature study on aluminium used as reflecting material in light reflectors, where I am particularly interested in the relation between the surface gloss and the treatment of the Al surface. Electropolishing will probably be the technique to focus on, but other gloss increasing techniques are also of interest. The intention is to start an experimental study where the surface texture (studied by AFM or others) and the top layer microstructure (studied by TEM) is correlated with the production and subsequent treatment of the Al surface. The final goal is to find the critical parameters for the gloss. I would greatly acknowledge the reception of important references in scientific literature and other sources on information covering this field.

Dr. Jostein Mardalen SINTEF Applied Physics N-Trondheim Norway

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1995

Electropolishing probably holds the most promise for really high specularity. But chemical bright dipping (in nitric-phosphoric acid), followed by anodizing, is the predominant method in use today for commercial reflectors, and is generally considered as good as electropolishing except for use on very high purity aluminum.

While the info is a bit dated, ASM International's Metals Handbook. Volume 5: Surface Engineering addresses the issue. Albright & Wilson offers their "Phosbrite" proprietary brightening solution, so they may have done some work of the type you are looking for. Hopefully our readers can point you to the literature you seek.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey