The technical specification DIN 50961 Fe/Zn 8b defines a specific electroplated zinc coating on iron or steel. This standard has largely been superseded by DIN EN ISO 2081
, though it remains a common reference in legacy engineering drawings. Google Groups Breakdown of the Designation : The substrate material is iron or steel. : The coating material is electrodeposited zinc.
: Represents the minimum required local thickness of the zinc coating, which is (micrometers).
: Indicates the type of supplementary chromate conversion coating. In this historical standard, "b" typically refers to blue (transparent/clear) chromating/passivation. Technical Summary Table Requirement Minimum Thickness 8 μm (approx. 0.00031") Critical for thread clearance on fasteners. Appearance Clear / Bluish Achieved through chromate passivation. Steel / Iron Standard "Fe" base material. Testing Standard DIN 50018 / ISO 9227 Evaluated via salt spray (NSS) or Kesternich tests. Modern Equivalent ISO 2081 Fe/Zn 8/A "A" denotes clear/blue passivation in modern ISO terms. Key Considerations for Implementation DIN 50961 Electroplated ZN Coating | PDF - Scribd
The designation DIN 50961 Fe/Zn 8b refers to a specific standard for electroplated zinc coatings on iron or steel parts. While this standard has largely been succeeded by ISO 2081, it is still frequently cited in engineering drawings and legacy specifications. 1. Decode the designation
The string of characters acts as a "recipe" for the finisher:
DIN 50961: The German standard for electroplated zinc coatings. Fe: The base material (Iron or Steel). Zn: The coating material (Zinc). 8: The minimum local thickness of the zinc layer (typically
b: The supplementary treatment, specifically indicating bright (blue) chromating. 2. Understand the coating thickness din 50961 fe zn 8b
The number 8 indicates that the component must have a minimum coating thickness of Provides moderate corrosion resistance. Suitable for indoor environments or sheltered outdoor use. Prevents "red rust" (oxidation of the steel base). 3. Identify the passivate (chromate)
The letter b signifies the visual and functional finish applied after the zinc plating:
Appearance: Often referred to as "Clear," "Blue," or "Bright" passivating. It has a slight bluish tint.
Function: Prevents "white rust" (oxidation of the zinc itself) and increases the durability of the finish.
Trivalent vs Hexavalent: Modern applications of "8b" usually utilize Trivalent Chromium ( Cr3+cap C r raised to the 3 plus power
) to comply with environmental regulations like RoHS, replacing the older, toxic Hexavalent ( Cr6+cap C r raised to the 6 plus power ) versions. 4. Compare with modern standards
If you are looking for the current equivalent to DIN 50961 Fe/Zn 8b, you should look at ISO 2081. The technical specification DIN 50961 Fe/Zn 8b defines
Equivalent code: Fe/Zn 8/A (where 'A' denotes the clear/blue finish). ASTM equivalent: Often compared to ASTM B633 Type III. ✅ Summary of Specs The part is steel with an electro-zinc layer and a bright/blue chromate finish. If you'd like, I can help you with: Finding local plating shops that handle this specification.
Comparing the salt spray test hours for this finish versus others. Looking up the RoHS status for specific manufacturers.
ASTM B633 Plating Specifications - Gatto Industrial Platers, Inc.
The code DIN 50961 Fe Zn 8b refers to a specific industrial standard for electroplated zinc coatings applied to iron or steel components. It is a critical specification used in manufacturing to ensure parts have adequate corrosion protection and specific aesthetic qualities. Breaking Down the Specification
Each part of the alphanumeric string "Fe/Zn 8b" provides essential information for the plating process: Din 50961 Fe Zn 8b - Google Groups
The code DIN 50961 Fe/Zn 8B refers to a specific technical standard for electroplated zinc coatings on iron or steel components, typically used for corrosion protection. Breakdown of the Code
According to standard DIN 50961 and related technical documentation from Ramo Group : Fe: The substrate or "basis metal," which is iron or steel. Zn: The coating material, which is zinc. Step 2: Zinc Electroplating Parts are immersed in
8: The minimum local thickness of the zinc coating, which is 8 micrometers ( ) (approximately 0.00031 inches).
B: The type of supplementary chromate conversion treatment. In this context, "B" traditionally signifies a bright (clear or bluish) chromate finish. Technical Context Din 50961 Fe Zn 8b - Google Groups
DIN 50961 Fe/Zn 8 B specifies a minimum 8-micrometer thick, blue chromate-passivated electroplated zinc coating on iron or steel for moderate corrosion protection. This German standard is often used for fasteners, though it is frequently superseded by DIN EN ISO 2081 or RoHS-compliant alternatives. For a detailed breakdown of this specification, visit Scribd. DIN 50961 Electroplated ZN Coating | PDF - Scribd
Parts are immersed in a zinc cyanide or alkaline non-cyanide (zincate) bath. A direct current reduces zinc ions onto the steel cathode. Process parameters (current density, temperature, bath agitation) are controlled to achieve the required 8 µm thickness evenly.
To certify that a batch meets DIN 50961 Fe Zn 8b, manufacturers perform the following tests:
Some specifications add a top organic or inorganic sealer to enhance corrosion resistance, though this is not required for "8b."