Services Offered

TFC's own formulations - After the molybdate coating is applied, the parts are submerged in a seal composed of chromates and phosphates that enhance the salt spray resistance of the coating. An organic coating, water dip lacquer, is applied as a final coat to protect the finish and improve appearance.

Similar to Econo Black, but this molybdate black is applied over a bright zinc plate to yield a glossy, plastic like black finish. The corrosion characteristics can be improved with a seal and/or lacquer as required.

Chromate coatings are chemical conversion coatings. The substrate metal participates in the coating reaction and becomes a component of the coating. The collaboration has a profound effect on the properties of the coating.

Among the metals commonly chromate are zinc, zinc die casting, aluminum and sometimes copper and silver. Chromate films are typically very thin, on the order or .0000001 in. and contribute no measurable thickness to the overall coating.

TFC offers the following Chromates: (and their resistance to white corrosion)

• Clear - Slightly iridescent blue appearance.
• Black - Select level of darkness.
• Yellow - Excellent paint base.
• Olive Drab - Dark green finish

Copper is most commonly used as an under-plate or strike because of its excellent adhesion and ductility. Deposited from a cyanide solution, copper is the best available deposit for plating direct on zinc die caste.

This finish is very similar to chrome in its appearance and applications. Parts are plated first with a bright nickel then flashed with tin to give a convincing appearance of a chrome-plated part. Finish is hard and durable. The alloy is a composite coating like a tin 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.

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 (see above)
• Watt's Nickel (Sulfamate)

Passivation of stainless steel is not electroplating, it is a non electrical process whereby the free iron is chemically removed from the surface of stainless steel. This prevents the formation of possible corrosion sites and the development of tightly adhering oxides. The 300 series alloys are generally preferred for Passivation, as some of the 400 series alloys will actually be discolored by the Passivation process.

Passivation imparts a limited neutral salt spray corrosion protection to the stainless steel, usually not much over 2 hours. Since different solutions are used to passivate different alloys, they must be properly identified. Mixing alloys may not only result in differences in appearance, but may result in some parts being destroyed.

Silver has an advantage of its relative low cost, but it is susceptible to tarnishing when exposed to sulfur in the atmosphere. Silver plating, in addition to being decorative, has the highest electrical and thermal conductivity of any metal. It is highly ductile, malleable, and solderable.

Silver tarnishes easily. Matte silver plate is used extensively for finishing electronic components where silver's mechanical properties of silver plate alone may not be enough and the design engineer feels that appearance may also be an important consideration.

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 Tin Plating:

• Bright Tin
• Matte Tin
• Tin/Lead 60/40, 90/10, 93/7Tin-Nickel

Parts are first chemically milled then chromated to give a dull almost olive drab finish. Chromate coatings are chemical conversion coatings. The substrate metal participates in the coating reaction and becomes a component of the coating. The collaboration has a profound effect on the corrosion properties of the coating, in excess of 96 hours to white corrosion. Special seals can be applied which increase corrosion resistance to over 500 hours.

Among the metals commonly chromate are zinc, zinc die-casting, aluminum and sometimes copper and Silver. Chromate films are typically very thin, on the order or .0000001 in. and contribute no measurable thickness to the overall coating.

Same as above but with a bright yellow iridescent finish.

Zinc plating is a soft, ductile, decorative, marginally solderable, corrosion-resistant finish. Unlike most other commonly plated metals, zinc protects the substrate by sacrificing itself and thus corrodes before the base metal. For corrosion protection, chromates are applied over the zinc. Chromates are chemical conversion coatings. The substrate metal participates in the coating reaction and becomes a component of the coating.

The collaboration has a profound effect on the properties of the coating. Among the metals commonly chromated are zinc, zinc die casting, steel, aluminum, and sometimes copper and silver. Chromate films are typically very thin, on the order of .0000001" and contribute no measurable thickness to the overall coating and contribute no measurable thickness to the overall coating.