. Because electroplating utilizes electric currents to deposit ions from a solution, the coating builds up unevenly depending on geometry.
(DIN 50979) are increasingly replacing pure zinc for automotive underhood applications because they offer 5–10x the corrosion resistance without thicker deposits.
When sourcing, ensure that the supplier provides RoHS-compliant trivalent passivation to meet current environmental regulations, and always consider the 8 μ m thickness when designing threaded fasteners.
: Dictates the minimum local thickness of the zinc layer, measured in micrometers (µm or microns). In this case, it guarantees a boundary layer of at least 8 µm on significant surfaces. din 50961 fe zn 8b
). The plated zinc layer must be at least 8 microns thick at any given reference point on the significant surfaces of the component. 5. B (The Chromate Conversion Coating / Finish)
The "8" in Fe//Zn 8B means the coating must be at least 8 μ m thick, typically measured at significant surfaces. This thickness provides a robust, sacrificial barrier against oxidation. Passivation (Chromate Conversion Coating - 'B')
: Indicates a zinc (Zn) coating with a minimum thickness of 8 micrometers ( Typical Applications of Fe//Zn 8b
Common use cases include:
The specification is a reliable, industry-standard coating for protecting steel components. It offers a moderate 8 μ m zinc layer for sacrificial corrosion resistance, finished with a blue/transparent passivate for improved performance and aesthetics.
According to standard DIN 50961 and related technical documentation from Ramo Group : : The substrate or "basis metal," which is iron or steel. Zn : The coating material, which is zinc. Zinc acts as a sacrificial anode
Zinc acts as a sacrificial anode, meaning it will corrode before the underlying steel does. An 8-micron zinc layer with a Type B clear/blue passivation typically provides the following performance in standard Salt Spray Testing (ASTM B117 / ISO 9227):
Understanding the technical requirements of Fe//Zn 8B ensures compliance in manufacturing and quality control. Thickness and Distribution
Some manufacturers add a sealer to further increase corrosion protection. Typical Applications of Fe//Zn 8b
