Zinc Flake Coating
Non-electrolytic anti-corrosion system for high-strength steel and fasteners.
Zinc flake coating is a non-electrolytic, high-performance, anti-corrosion coating system composed of zinc and aluminum flakes in an inorganic binder. It is a modern alternative to traditional methods like electroplating and hot-dip galvanizing, offering superior protection without the risk of hydrogen embrittlement.
Request TDS / QuoteKey Properties
Superior Corrosion Resistance
Zinc flake coatings use both barrier and sacrificial protection. The aluminum flakes act as a barrier, while the zinc flakes corrode first to protect the underlying steel. It offers significantly longer Salt Spray Test (SST) resistance compared to standard zinc plating.
Thin, Uniform Layer
The coating is very thin, typically 5 to 15 um, which prevents thread interference and ensures the proper function of nuts and bolts.
No Hydrogen Embrittlement
Since the process does not use an electric current, it completely eliminates the risk of hydrogen embrittlement, making it ideal for high-strength steel fasteners, springs, and other critical components.
High Temperature Resistance
Zinc flake coatings can withstand temperatures higher than many other coatings, making them suitable for automotive engine and exhaust components.
Common Applications / Use
The automotive sector is one of the largest users of zinc flake coatings, which have become a chromium-free alternative to electroplating.
High-Strength Fasteners
Zinc flake is essential for bolts, grade 10.9 and 12.9, nuts, and springs, which are prone to hydrogen embrittlement from electrolytic processes.
Chassis And Underbody Parts
Components exposed to harsh road conditions, such as road salt and moisture, are coated to ensure durability and extend vehicle lifespan.
Fuel And Brake Systems
Items like brake discs, calipers, brake lines, and fuel tanks are coated for corrosion and temperature resistance.
Engine Components
Parts in the engine compartment and exhaust systems benefit from the coating's high-temperature resistance.
Galvanic Corrosion Prevention
Zinc flake-coated fasteners are compatible with hot-dip galvanized components, preventing galvanic corrosion that can occur when using dissimilar metals.
Surface Preparation
Degreasing: This initial stage removes all organic contaminants, which are any oil-based soils.
Rust and scale removal: This step is essential for removing inorganic contaminants that are products of corrosion.
Application Details
Once the surface is clean and dry, the zinc flake coating is applied. Common application methods include dip-spin coating and spraying.
Dip-spin coating: Ideal for bulk processing of smaller parts like fasteners. Parts are placed in a basket, dipped into the coating solution, and spun to remove excess material.
Spraying: Used for larger or complex-shaped parts.
Ready to specify Zinc Flake?
Our technical team will help with system selection, TDS, and project support.