Metal finishing Q&As since 1989

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Black Chem Film or Conductive Finish

 

I am looking into the possibility of not masking parts anymore. We have a part that is black anodized and one side is masked to allow electrical conductivity. The only reason the rest of the part is black is because of aesthetics. Chem Films are electrically conductive. Is there a Black Chem Film on the market anywhere. There is gold, and it just looks like a die additive, why not black? Cost and thermal dissipation are issues, so a black chrome is not the answer.

Russ Jenkins
- Camarillo, California

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Russ,

I don't think you can dye a chem film. Even if you could dye it black, heat would destroy the coating. I can suggest two places to try for some possibilities. Metalast has a process to bring conductivity back into the anodized parts, and Sanchem may have a black coating of some type available.

Drew Nosti, CEF
Anodize USA

Ladson, South Carolina

How about black electroless nickel?

Todd Osmolski
- Charlotte, North Carolina, USA
 

There is a gold chem film, so why not a black chem film? The gold chem film parts we get back are greenish or reddish, I would assume from a dye agent. The part should not heat up beyond what the Chem Film can handle. Basically I am looking for a way around the costs of masking, yet keeping the aesthetics for my customer.

Russ Jenkins
- Camarillo, California
 

Why--Because it is not a dye, it is a reaction between the aluminum and chromic acid with the help of several promoters, accelerators, inhibitors and etc. The different colors are because of differences in formulation and operating conditions of time,concentration, temperature with a small effect from the surface finish and activation.

James Watts
- Navarre, Florida
 

Electrically conductive black coatings are available in many forms. Try Acheson.

Leonard Allison
- Port Huron, Michigan