Types Measurement Material Finishes
Fastener Finishes
Protecting your fasteners.
Fastener coating, plating and finishes adds an extra layer of corrosion protection to your fastener assemblies. Below is everything you will need to know about all the different available options.
Black Iron
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This bare metal surface has no finish for improving appearance or corrosion resistance. Often the surface has been oiled, which improves lubricity. Bright steel fasteners can be used indoors or in outdoor environments where corrosion protection is not an issue. This finish is also known as B.I.
Galvanized Iron
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This finish, also known as G.I. is the standard for many hardware fasteners. The zinc protects the steel from corrosion. It is a popular finish because of its protection, cheapness, and ease of coating. Slightly less corrosion resistant than yellow zinc, it is a versatile finish that is best used indoors. This finish should not be used in marine or high salt spray environments.
Yellow Plated
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Similar to bright zinc finish, this iridescent electroplated zinc, also known as tetanized plated, provides very good corrosion resistance and protection against rust, more resistant than bright zinc. This finish should not be used in marine or high salt spray environments.
Hot Dip
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Hot dip galvanizing adds a layer of corrosion resistance by dipping fabricated steel into a kettle containing molten zinc. The hot dip process creates a tightly bonded alloy for superior corrosion resistance and harsh environment applications. Due to the thickness of the coating HDG bolts are only compatible with HDG nuts.
Black Oxide
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Black oxide is the industry standard for high tensile fasteners. This is an extremely thin oxidation created on the surface of the fastener. It has almost no corrosion resistance but it is attractive and does not affect the dimension of the fastener, ideal for use on sprockets, gears, and couplings, where dimensions are critical, and on things that are maintained and regularly oiled like machinery and equipments.
Nickel Plated
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Nickel electroplating provides corrosion and wear resistance in a fastener. This plating is beneficial if there is likely to be wear or friction in the fastener as nickel does not flake or chip like other finishes. It is also provides an even coating on any fixing, even in recesses or holes. Nickel plated fasteners are most commonly used in the marine, gas and oil industries.
Chrome Plated
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Chrome plating adds a thin layer of chromium to the fastener. The plating provides a shiny decorative look and an extra layer of corrosion resistance. It also helps prevent galling and improve oxidization resistance. Due to its high level of corrosion resistance it is often used in the automotive industry.
All Information provided in this page serves as a guide and not for reference purposes. Citi Bolt Group does not guarantee or warrant the accuracy or reliability of any information in our fastener guide. Citi Bolt Group accepts no responsibility for any loss or damage whatsoever resulting from reliance on the information provided.