Finishes on Fasteners

Note that not all of these finishes are available to Trojan Special Fasteners and a number of unmentioned ones are. So, if in doubt, please always ask us and we'll find out if our subcontractors can finish your ordered fasteners in the way you need and want.

Why do we plate or coat fasteners?

Feature Benefit Description
Absorbs Light & Energy Ensures compliance with industry standards Black electroless nickel plating absorbs light and energy essential to many manufacturing processes in industries such as aerospace, automotive and aviation.
Conducts Electricity Cost effective and efficient conductivity solution Silver plating can be used to enhance electrical conductivity which makes it useful in the manufacture of electronic components.
Enhances Appearance A cheaper way to improve aesthetics Jewelry is often plated with a thin layer of a precious metal to make it more desirable.
Forms a Protective Barrier Plated parts can last longer and need to be replaced less frequently, and are more likely to hold up under extreme conditions. Many types of industrial electroplating create a barrier on the substrate that protects it against atmospheric conditions such as corrosion.
Increases Hardness Plated surfaces are less susceptible to damage when struck or dropped, which can increase their lifespan. Electroplating is sometimes used to make brittle materials stronger and more durable.
Increases Thickness It improves overall quality and increases longevity of the substrate. Palladium plating is becoming an increasingly popular choice in manufacturing processes where extreme thickness is required.
Prevents Tarnishing Products such as silverware retain their attractiveness and hold their value over time. Some types of electroplating protect against premature tarnishing in certain kinds of metals and also reduce the likelihood of scratching.
Promotes Adhesion It provides a smooth and uniform surface finish. Copper plating is an ideal solution for providing an undercoating that facilitates adhesion with additional coatings.
Reduces Friction Nickel plating improves performance and reduces premature wear and tear. Nickel plating can reduce the build-up of friction in certain materials such as electrical connectors.
Resists Heat Plating with these metals protect engine parts and components from damage caused by extreme temperatures, which can increase their lifespan. Plating processes such as gold or zinc-nickel are capable of withstanding extremely high temperatures.

If you're looking for a corrosion-resistant finish for your fasteners, zinc plating may be the perfect choice for you. Zinc plating is a widely used process for coating metal components with a protective layer of zinc, which acts as a barrier to rust and corrosion. It's a great way to protect your fasteners from the elements and extend their service life.

Zinc Trivalent Processes

Trojan Special Fasteners Ltd has access to a number of subcontractors based in the Midlands that can offer Rack and Barrel Plating. These Trivalent Processes are both Reach and RoHS compliant because they are free from cyanide and other strong complexing materials. These are hexavalent (Chrome VI) free. They are ideally used for non-automative applications where we need to eliminate hexavalent chrome.

  • Trivalent Clear Passivation - gives a bright silver sheen to nuts
  • Heavyweight Trivalent Passivation - gives an iridescent shine to nuts
  • Trivalent Black Passivation - gives fasteners a black appearance

Why is Zinc Trivalent more Desireable?
Hexavalent Chrome (Chrome VI) is a carcinogen and even though tiny amounts are used in the plating process, companies are increasingly specifying RoHS compliant plating in order to eliminate their use.

Zinc Hexavalent Processes
Hexavalent processes are available and it is assumed that you understand these are not RoHS compliant due to the hexavalent nature of this kind of plating.
These are used where corrosion resistance is of high importance - the passivate portion means that if the plated area is scratched, the chromate layer flows back and 're-passivates' the area. In essence, it means that this is a form of self-healing plating.

  • Hexavalent Zinc and Yellow - gives a golden yellow colour
  • Hexavalent Black Passivation - gives fasteners a black appearance
  • Hexavalent Olive Drab Passivation - gives an olive green colour

So, how is zinc plating done?
It's a fairly straightforward process. First, the fasteners are immersed into an electrolytic solution, which is usually made up of an acid, a zinc salt and other additives. An electric current is then passed through the solution, causing the zinc ions to deposit onto the fastener. This creates a thin layer of zinc that protects the fastener from corrosion.

Why use zinc plating?
Zinc plating is an effective way to protect your fasteners from the elements. It's also relatively inexpensive, making it an economical choice for many applications. Plus, it's easy to apply and can be done quickly, making it a great option for those who need fasteners that are ready to use right away.

What are the issues with using zinc plating?
Unfortunately, there are some potential issues with using zinc plating. For one, it can be susceptible to cracking if the fasteners are exposed to harsh conditions. It's also not as durable as other coatings, such as galvanizing, so it may be necessary to re-plate the fasteners periodically. Additionally, zinc plating is not suitable for use in applications where food or water will come into contact with the fastener, as it can be toxic in large doses.

In terms of safety, zinc plating is generally considered safe for use in most applications. It's important to keep in mind, though, that the fasteners should be thoroughly rinsed after plating to reduce the risk of toxic exposure.

Finally, if you're looking for a reliable source of zinc plated fasteners, look no further than Trojan Special Fasteners Ltd. We offer zinc plating on all ferrous nuts and can provide fasteners that are ready to use right away.