Black Chrome Again
Can you give me a procedure for the black chromium plating process?
Share
Q. I would like to know more about the black chromium plating process. Can you give me a procedure for the process? T.B.
A. Black chrome has been used for many years, primarily as a decorative finish. Most of the black chromium plating processes are proprietary in nature. The major problem with the process is getting consistent color and deposit characteristics. Sometimes a black chromium deposit is plated over a regular chromium deposit. There are proprietary processes based on both hexavalent and trivalent chromium.
Featured Content
A typical bath formulation is given in the table below:
| Component | Concentration |
|---|---|
| Chromic acid | 250g/L |
| Acetic acid | 260 g/L |
| Barium acetate | 7.6 g/L |
| Operating Conditions | Range |
| Temperature | 100°F |
| Current density | 40-90 ASF |
While the above formulation will give you a decent finish, you will be much better off if you use a proprietary formulation.
RELATED CONTENT
-
A Chromium Plating Overview
An overview of decorative and hard chromium electroplating processes.
-
Cleaning, Pretreatment to Meet Medical Specs ISO 13485 or FDA 21 CFR820
Maximilian Kessler from SurTec explains new practices for industrial parts cleaning, metal pretreatment and decorative electroplating in the medical device industry.
-
Stripping of Plated Finishes
The processes, chemicals and equipment, plus control and troubleshooting.
