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→Selective Electroplating
=====<!--7.1.1.1.2-->Non-Precious Metal Electrolytes=====
The most important non-precious metals that are deposited by electroplating are: Copper, nickel, tin and zinc as well as their alloys. The deposition is performed in the form of pure metals with different electrolytes used (<xr id="tab:Typical Electrolytes for the Deposition of Non-Precious Metals"/><!--(Table 7.4)-->).
*Copper electrolytes <br>Copper electrolytes are used for either depositing an intermediate layer on strips or parts, for building up a printed circuit board structure or for the final strengthening during the production of printed circuit boards.<br />
'''Electroplated Parts'''
<figure id="fig:Electroplated Parts">[[File:Electroplated Parts.jpg|left|Figure 1: Electroplated Parts]]</figure>
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Besides others the following layer parameters are typically monitored in-process and documented:
Special high performance electrolytes are used in selective electroplating to reach short plating times and allow a high flow rate of the electrolyte for a fast electrolyte exchange in the actual coating area.
For a closely targeted electroplating of limited precious metal coating of contact springs, so-called brush-electroplating cells are employed (<xr id="fig:Brush Tampon plating cell"/><!--(Fig. 7.1)-->). The “brush” or “tampon” consists of a roof shaped titanium metal part covered with a special felt-like material. The metal body has holes in defined spots, through which the electrolyte reaches the felt. Also located In the same spots is the anode, consisting of a fine platinum net. The pre-stamped and in the contact area pre-formed contact spring part is guided under a defined pressure over the electrolyte soaked felt material and gets wetted with the electrolyte. This allows the metal electroplating in highly selective spots.
<figure id="fig:Brush Tampon plating cell">
[[File:Brush Tampon plating cell.jpg|right|thumb|Figure 1: Brush (or “Tampon”) plating cell; 1 Strip; 2 Anode; 3 Electrolyte feed; 4 Felt covered cell]]
</figure>
For special applications, such as for example electronic component substrates, a dot shaped precious metal coating is required. This is achieved with two belt masks running synchronous to the carrier material. One of these two masks has windows, which are open to the spot areas targeted for precious metal plating coverage.
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Copper, copper alloys, nickel, nickel alloys, stainless steel
[[File:Dimensions and Tolerances.jpg|left|Dimensions and Tolerances]]
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Mechanical properties and dimensional tolerances of the carrier materials follow the typical standards, i.e. DIN EN 1652 and 1654 for copper and copper alloys. Depending on the application, the following parameters are tested and recorded (see also: Electroplating of parts):