Zinc-Plated Fasteners
Electroplated zinc is a thin sacrificial coating for indoor and mild outdoor use. The color, clear, yellow or black, comes from the passivate, not the grade.
Zinc plating facts
| Typical thickness | About 5 - 8 micrometres (0.0002 - 0.0003 in) |
|---|---|
| Passivates | Clear/blue, yellow, black; trivalent is RoHS-compliant |
| High-hardness parts | Hydrogen embrittlement relief bake required (roughly HRC 39 and up) |
These tables carry the same figures as the printed sheet below.
The printed sheet
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Text version of this sheet
ASTM F1941 · electroplated zinc on fasteners
What it is
FIELD IDENTIFICATION
Electroplated zinc is a thin sacrificial coating for indoor and mild outdoor use. The color, clear, yellow
or black, comes from the passivate, not the grade.
CLEAR / BLUE
YELLOW
BLACK
Electroplated zinc - color is the chromate, not
the grade
Zinc plating facts
Typical thickness
About 5 - 8 micrometres (0.0002 - 0.0003 in)
Passivates
Clear/blue, yellow, black; trivalent is RoHS-compliant
High-hardness parts
Hydrogen embrittlement relief bake required (roughly HRC 39 and up)
Key points
Color does not identify Grade 5 vs Grade 8.
Governing standards: ASTM F1941/F1941M-16(2025); ISO 4042:2022. Editions shown are the latest confirmed as of September 2026. The drawing and the governing standard
always take precedence over this sheet.
torquing any fastener. Verify the current governing standard, project documents, OEM requirements, size, thread, coating and lot certification. To the fullest extent permitted by law, The Fastener App disclaims liability
arising from reliance on this reference.
Fastener Guide reference FG-1865A0 · thefastenerapp.com/fastener-guide/technical-reference/zinc-plated-fasteners · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.
