The authoritative public forum
  for Metal Finishing since 1989
-----

Polishing black anodized steel parts

My company recently had steel parts treated with black anodize. The parts came out somewhat dull in appearance and the customer was looking for more of a shinier look in the black anodize. Is there any way to add a shine to the parts? I tried heating the parts and then dipping them in oil. It seemed to work, but I was just wondering if there was any other procedure that might help.

Thanks,

Justin Casey
machinist - Manchester, Massachusetts
2004

---

It is very unlikely that the parts were black anodized because steel cannot be anodized. The treatment was propably black oxide. Oil will help, but may not give you a really shiny look if the treatment was a cold blackening as opposed to a genuine hot black oxide treatment.

Hot black oxide plus oil on a bead blasted surface will give you a dark, rich, black finish which looks from a little distance like black enamel. Polishing the steel to a bright finish before black oxiding will give you a deep onyx finish. Polishing after black oxide will probably remove the black oxide finish.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004