Benefits of Plating

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Nickel Plating is a yellowish white, hard reflective finish used for wear resistance, solderability, or dimensional restoration. Nickel plate is often applied over copper and under chromium for a decorative finish. For applications requiring bright nickel, there are other considerations. Nickel brighteners increase brightness, internal stress, and lower the ductility.

It is best to avoid specifying bright nickel if the parts are to be bent or crimped after plating. For those instances, a Watt's nickel (nickel sulfate with little or no brighteners) is used. This semi bright nickel has a more satiny finish than bright nickel but is more ductile. If heat shock or minor bending of the parts is anticipated it would be better to specify semi bright nickel in order to reduce the risk of the plating flaking off.

TFC offers the following Nickel Plating:

Bright Nickel
Electroless Nickel
Watt's Nickel (Sulfamate)

Tin Plating

Tin plating is normally done to impart solderability to variety of base metal substrates. Tin is a silvery, blue-white metal that is ductile, solderable, and covers very well. The solderability of time can be affected by the substrate, since several metals tend to react with and migrate into the tin forming relatively non-solderable intermetallic layers. Of particular concern is tin plating over brass or zinc die-cast. The zinc will migrate into the tin and severely limit the shelf life of the finished parts.

The migration can be mitigated by the common practice of applying an undercoat of copper or nickel or a combination of copper with a flash of nickel through which the zinc cannot migrate. Matte tin generally has better solderability, but bright tin is specified more because of its appearance. Tin does not tarnish easily, making it a good choice as a decorative finish.

TFC offers the following Nickel Plating:

Bright Nickel
Electroless Nickel (see above)
Watt's Nickel (Sulfamate)

Electroless Nickel

Unlike conventional electroplating, no electrical current is required for deposition. The electroless bath provides a deposit that follows all contours of the substrate exactly, without building up at the edges an corners. A sharp edge receives the same thickness of deposit as does a blind hole.

The most widely used engineering form of electroless plating is, by far, electroless nickel. Electroless nickel offers unique deposit properties including uniformity of deposit properties in deep recesses, bores and blind holes. Most commercial deposition is done with an acid phosphorus bath owing to its unique physical characteristics, including excellent corrosion, wear and abrasion resistance, ductility, lubricity, solderability, electrical properties and high hardness.

TFC offers different types of Electroless Nickel

Low Phos- A hard deposit approaching hard chrome with no heat treatment necessary for hardness. Comparable to boron electroless nickel. This deposit is used mainly for its hardness and wear properties.
Mid Phos- By far the most widely used deposit. It has a bright uniform appearance and is used for both decorative and electronic applications.
High Phos- Compressively stressed deposits with excellent adhesion, ductility, and superior corrosion resistance.