Engineering Tools
Reference data for specifying and sourcing fasteners correctly — the numbers a procurement or design engineer actually needs.
Plating & coating reference
Corrosion resistance and typical use case by finish type.
| Finish | Typical thickness | Salt spray resistance | Typical use |
|---|---|---|---|
| Zinc plated (Fe/Zn 5) | 5 µm | 12 hrs to white rust | Indoor, light-duty |
| Zinc plated (Fe/Zn 8) | 8 µm | 48 hrs to white rust | General purpose |
| Zinc plated (Fe/Zn 12) | 12 µm | 96 hrs to white rust | Outdoor exposure |
| Hot-dip galvanized (HDG) | 45–55 µm | 200+ hrs to red rust | Structural, heavy outdoor |
| Dacromet / Geomet | 5–8 µm | 500+ hrs, no H-embrittlement risk | Automotive, high-spec |
| Black oxide | <1 µm | Minimal — cosmetic/oil-retention only | Indoor, low corrosion risk |
| Passivated (SS) | Chemical treatment, not a coating | Restores inherent SS corrosion resistance | Stainless steel fasteners |