Copper and Bright Dips
Q. Can you suggest a good formulation for bright dipping of copper alloys? I require a bright dip that will give me good polishing of the copper surface. S.L.
A. There are many different formulations for bright dipping of copper and copper alloys. Almost all of the classic formulations involve the use of sulfuric acid chromic acid and nitric acid. If you are looking for a formulation that will give you greater smoothing, a different formulation should be used. The table below shows a typical bath that will give you a very smooth bright finish.
|Nitric acid (1.42 specific gravity)||20%|
|Acetic acid (1.05 specific gravity)||25%|
|Phosphoric acid (1.70 specific gravity)||55%|
An alternative product for passivation...
Masking is employed in most any metal finishing operation where only a specifically defined area of the surface of a part must be exposed to a process. Conversely, masking may be employed on a surface where treatment is either not required or must be avoided. This article covers the many aspects of masking for metal finishing, including applications, methods and the various types of masking employed.
The processes, chemicals and equipment, plus control and troubleshooting.