Military fasteners must maintain integrity in harsh environments—saline, chemically aggressive, thermal cycling, and vibration conditions. Plating shields fasteners from corrosion, wear, seizing, and galvanic damage, delivering mission-critical performance and reliability.
1. Enhanced Corrosion Resistance
- Zinc-nickel plating offers superior corrosion protection, lasting up to 5× longer than standard zinc and approaching cadmium performance—without the environmental hazards.
- Cadmium plating, a long-time military standard, is still used due to excellent corrosion resistance and lubricity, especially near aluminum alloys—but its use is restricted due to toxicity concerns.
2. Galling Prevention & Strength Retention
- Nickel and electroless nickel plating reduce galling and improve wear resistance, especially under high-load and vacuum conditions common in military hardware.
- Silver plating minimizes friction and enhances conductivity in RF or electrical components.
3. Protection from Dissimilar Metal Contact
- Fasteners often contact multiple materials—steel, aluminum, composites—which can lead to galvanic corrosion. Plating acts as a barrier, preventing direct metal-to-metal interaction.
4. Specialized Plating for Extreme Conditions
- Zinc-flake coatings provide high corrosion protection (240–1,500 hrs salt spray), avoid hydrogen embrittlement in high-strength parts, and comply with ISO 10683 standards.
- Chromate conversion coatings (Alodine) passivate aluminum and zinc-plated parts and aid paint/adhesive adhesion without compromising conductivity.
Military Plating Types
| Plating Type | Primary Benefit | Military Application |
|---|---|---|
| Zinc‑Nickel | High corrosion resistance, eco-friendly alternative to cadmium | Marine, ground vehicles, avionics |
| Cadmium | Sacrificial corrosion protection, high lubricity | Aerospace heritage systems, legacy platforms |
| Electroless Nickel | Non-galling, wear-resistant, good corrosion protection | High-load mechanisms, vacuum environments |
| Zinc Flake | Thick, uniform coating without hydrogen embrittlement | High-strength 10.9/12.9 bolts |
| Chromate Conversion | Passivation, paint adhesion, conductivity | Aluminum frames, painted assemblies |
Best Practices for Military Plating
- Match finish to environment: salt, chemicals, abrasion, electrical needs, and temperature.
- Confirm plating spec compliance: MIL‑DTL‑L‑85085 for Zn-Ni, QQ‑N‑290A for nickel, ISO 10683 for zinc flake.
- Test for hydrogen embrittlement on high-tensile steel.
- Request certs and inspection records, including plating thickness and bath quality.
Why It Matters
Proper plating protects fasteners that hold critical assemblies—armor, aircraft, vehicles, electronics. Incorrect finishing risks corrosion, joint failure, and mission compromise.
At Metric Bolt, we stock military-grade plated fasteners—including zinc-nickel, cadmium, electroless nickel, and zinc flake—with full MIL-spec compliance, traceable certification, and technical support for your application.
Need expert guidance on plating selection or certified orders?
Contact Metric Bolt for custom specs, plating documentation, or to become your go-to fastener supplier.
