Copper is suitable for many surface finishing processes. Among other things, copper can also be electroplated. We have summarized the special features of electroplating copper below.
Basics about copper
Copper is a relatively soft metal and is therefore very easy to process. In addition, it has excellent properties against oxidation, more on this under "Copper corrosion ".
- Also read - pouring copper
- Read also - Pressing copper
- Also read - Milling copper
Copper and electroplating
When electroplating with copper, a distinction must be made between the coating of other metals with copper and the coating of copper itself. Copper can be electroplated with different metals. The most common is the electroplating of copper:
- with copper
- with nickel
- with chrome
In particular, if you want to chrome-plate copper, nickel-plating is recommended in advance. This has such a positive effect on the surface quality that the chrome adheres very well.
Electroplating is a coating technique that can be used for almost all metals. For example, aluminum can also be chrome-plated, copper-plated or nickel-plated with the help of electroplating.
The process of electroplating
Conventionally, the metal to be coated is connected to the positive pole (the anode). The metal to be electroplated is connected to the negative pole (the cathode). The current detaches metal ions from the metal on the anode, and these are then deposited on the metal on the cathode.
The electrolyte for electroplating
Depending on the strength of the current, voltage and time, a coating of different thickness is then created. The bath (the electrolyte) consists of an acidic or alkaline compound, depending on which metal is to be electroplated with. For example, an aqueous chromic acid base H2CrO4 with sulfuric acid H2SO4 as a catalyst is used for chrome plating.
For nickel plating, the nickel electrolyte consists of an aqueous solution containing nickel salts. For copper plating, copper sulfate is first obtained (with sulfuric acid), which is then crushed and dissolved in water.
Alternatives to plating by immersion: tampon plating
The specialist trade now also offers tool sets in which the electrolyte is applied with a sponge or tampon. The sponge carrier can be adjusted to the power requirement. Depending on the aids used, this process is also known as tampon electroplating.Tips & Tricks Before you can actually start electroplating, you have to condition the workpiece. That means you need to grind, polish, and brush the copper workpiece. It may also be necessary to etch the copper to remove the oxidation layer. In addition, the surface must also be degreased.
If copper is to be chrome-plated and it is first nickel-plated, these steps must be repeated in some cases between the galvanizing processes. Not every metal can be electroplated at home. For example, chromium plating produces highly toxic fumes and the electrolyte must be cleaned in accordance with the regulations.
In model making, gold is also used in this way. Parts to which electricity is later carried (current collectors, plugs) become resistant to sparks.