Ask the Expert Question-and-Answer Archive
(Hard Chrome Plating)
by Larry Zitko, ChromeTech, Inc.
Plating/Stripping Chromium on Tungsten
Q. We have some tungsten parts which have been plated with chromium plating.
The plating needs to be removed and replaced.
First - What stripping solution/method would be less likely to etch the
base material of the tungsten part?
Second - What is the best activation to use for chrome plating on
I have no experience with plating chrome on tungsten, and could not find any
reference of it in my library or on-line.
However, I did find a reference to plating nickel on tungsten. In the "Shop
Problems" section of the March 1987 issue of Metal Finishing Magazine, a
reader asked how to plate nickel on needles made of tungsten alloy. The
author provided the following sequence:
- Anodically etch in 4 oz/gal potassium hydroxide solution, 120-140 deg
F. for 2-3 minutes.
- Neutralize in 10% sulfuric acid solution.
- Strike immediately in 33 oz/gal chromium plating bath with 100:1
- Immerse in 20% hydrochloric acid for 2-5 sec.
- Nickel sulfate strike.
- Nickel plate.
If you consider the first 4 steps and ignore the remaining steps, it looks
similar to your application, except that your thickness of chromium would
undoubtedly be greater than the chromium strike.
I hope this research and reference will be of assistance.