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Black Finish for Aluminum in a Vacuum System

2006

I have a unique finishing problem. I have some aluminum parts that must have a black finish (to provide contrast for an image recognition system). These parts go into a Vacuum system so I cannot tolerate a very porous surface typical of anodizing. I also cannot have any organics that might outgas and the parts will sit at 120C for most of their operational life.


Does anybody have any suggestions?

Michael Martin
- Madison, Wisconsin

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First of two simultaneous responses --

Type III Class 1 anodize. Thicknesses in excess of .002" on aluminum alloy 6061 will produce very dark grey-black color without introducing dye.

Bill Grayson
metal finishing - San Jose, California, USA
2006

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Second of two simultaneous responses --

I see two options. Two step anodizing (architectural) which gets its color from electroplated metals after the anodize. I do not think that a true black is one of the options, however. Second would be to black chrome plate it.

James Watts
- Navarre, Florida
2006

You can use black nickel or black chrome,or you can copper plate it(zincate it before) and then treat it like copper(You can use persulphate,copper nitrate [affil links] or potassium polysulfide process). Good luck and hope it helps!

Goran Budija
- Cerovski vrh Croatia
2006

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Given your requirements, it seems certain that you will not retain the Aluminium surface.
Your choices could be Black Nickel, Black Chrome, Black oxide or Black Titanium.

Kas Amadi
- Dayton, Ohio
2006