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Dark Finish to Stainless Steel

I'm looking for a process to give a dark, attractive, finish to Stainless Steel parts and fasteners. Preferably with little to no build-up (no paint) and the simpler the process the better. I've seen black chrome, but is it applicable to Stainless Steel? And of course this process is not easily scalable to small production. I've read/tried two that sounded great, but neither have worked. A)ferric chloride ⇦ this on eBay or Amazon [affil links] - solution used to etch copper did nothing b)Silver Nitrate- after oxidization, was easily rubbed off.

Standing by

Dirck Donson
- Little Rock, Arkansas
2003

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Check with Prismatic Stainless Steel [from B&M Finishers, a finishing.com supporting advertiser] and see if they can anodize your parts. Yes you can anodize SS, but it is a proprietary process. See if this process will work for you. There is one other, but I can not remember their name. Theirs is a HIGH voltage process. Both yield a shade of black. Try the search engine at this site.

James Watts
- Navarre, Florida
2003

Dirck, Yes,black chromium can be plated on SS material.All metal preparation baths should be similar for plating Nickel/Hex chrome on mild steel except,for SS,a wood's nickel strike would be needed before the bright nickel plating for reasons of adhesion problems. Alternatively,if appearance is not a big issue,black chrome can be directly plated to SS material provided the electrocleaning is anodic and an activation step is done prior to black chroming.The activation step may consists of a simple immersion process at room temperature,about 30 seconds in 0.1% HCl and 1% H2S04 solution.This would remove the oxide layer that readily form on most SS material and leave an activated surface which is excellent for black chromium plating.I have plated SUS304 wire (2 mm diameter)this way and by the way,apply some machine oil on the surface after black chroming to give it a brighter look.Good Luck.

SK Cheah
- Hong Kong
2003