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  for Metal Finishing since 1989
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Black finish on Aluminium

1999

Hi,

1) We occasionally produce aluminium parts for optical purposes, lens holders for example. We need to find a suitable method to blacken their surface with a non-reflective, non fluorescent black matte finish. Preference for a simple method, dipping, anodizing, etc. No problem if further dying with a paint is needed. Should not make substantial changes to dimensions. Another option would be to coat the aluminium with a thin layer of copper (we suppose copper is easier to blacken, but how?) As a last resort we used a matte black spray paint but unfortunately some of them are slightly fuorescent.

2) Can you give us the complete reference of the book on metal finishing techniques edited by McGrawHill? We cannot find it here. Out of print? Thanks

Pedro Fernandes
- LISBOA

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1). The dimensional change in anodizing is inherent, not a matter of technique; when you convert aluminum to aluminum oxide, you gain thickness. Normally approx. 40-50 percent of the specified thickness.

2). Unfortunately, I don't know what book you're referring to.

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

Mr. Pedro Fernandes ..... Biodinammica...... Lisboa When Anodizing to get the disired apparpence material is very important, After that there is the type of pretreatment Such as non etch or etch, etch is very good for a matte finish, my best success has been with a sulfuric Acid type solution black dye color is controller by depth of anodizing, temperture and concertration of dye.

Chris Snyder
plater - Charlotte, North Carolina
1999