Choose DIN 50961 Fe/Zn 8b for steel parts requiring a thin zinc layer (8 µm minimum) with a decorative, passivated finish (blue or yellow) for mild indoor corrosion protection. Confirm with your plater whether blue or iridescent yellow is intended, and ensure trivalent chromium is used for regulatory compliance.
As global manufacturing has streamlined, DIN 50961 has transitioned toward international standards. Additionally, environmental regulations like (Restriction of Hazardous Substances) and REACH have pushed the industry away from traditional hexavalent chromium ( Cr6+cap C r raised to the 6 plus power ) Type B finishes toward trivalent chromium ( Cr3+cap C r raised to the 3 plus power ) alternatives.
on iron or steel parts, typically used for fasteners and small hardware Specification Breakdown din 50961 fe zn 8b
ASTM B633 Plating Specifications - Gatto Industrial Platers, Inc.
DIN 50961 Fe/Zn 8B a technical specification for an electroplated zinc coating Choose DIN 50961 Fe/Zn 8b for steel parts
The designation DIN 50961 Fe/Zn 8b describes a specific electroplated zinc coating on steel (or iron) parts. The standard (DIN 50961, now largely superseded by DIN EN ISO 4041 but still widely used in industry) defines the coating thickness, corrosion resistance requirements, and post-treatment (chromating).
Internal, non-exposed steel components.
: 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
Low-current density areas (internal recesses, blind holes, inside channels) may receive less zinc. The standard dictates that the The standard (DIN 50961, now largely superseded by
The 'B' indicates the type of post-treatment, or passivation, applied after the zinc plating: