our Metal Finishing

Zinc-Nickel Plating Services.

Superior corrosion protection for aerospace, automotive, and defense applications requiring extreme durability

Lead Time

10-14 days

Materials

Steel Substrates

Certifications

ISO 9001, Nadcap

Industries

Aerospace, Defense, Automotive

What Is Zinc-Nickel Plating?

Zinc-nickel plating is an advanced electroplated coating that deposits an alloy of zinc (typically 85-88%) and nickel (12-15%) onto steel substrates. This alloy coating provides corrosion resistance 10-15 times superior to standard zinc plating.

The result is a coating that significantly outperforms standard zinc, particularly in harsh environments involving salt spray, humidity, high temperatures, and chemical exposure. The coating is typically applied at 0.0002″ to 0.0005″ thickness and finished with a trivalent chromate conversion coating for enhanced protection.

10-15×

Better Protection

1000+

Hours Salt Spray

300°F

Thermal Stability

Our Process

The Zinc-Nickel Plating Process.

Our precision-controlled process ensures consistent, high-quality results meeting the most demanding specifications.

Total Process Time: 4-6 Hours

Part Cleaning & Preparation

Parts are thoroughly cleaned to remove oils, greases, rust, and contaminants. Multiple cleaning stages ensure surface is chemically clean for proper plating adhesion.

Activation

Acid activation removes surface oxides and prepares steel surface for plating. Critical for achieving strong metallurgical bond between substrate and coating.

Zinc-Nickel Electroplating

Parts are immersed in alkaline zinc-nickel plating bath. Electric current causes zinc and nickel to co-deposit as an alloy coating. Plating time: 15-45 minutes.

Rinsing

Multiple rinse stages remove plating solution and prevent contamination of subsequent processes.

Chromate Conversion Coating

Parts are immersed in trivalent chromate solution forming a protective layer. Available in clear, yellow/gold, or black finishes.

Baking (High-Strength Steels)

High-strength steel parts (>180 ksi) are baked at 375°F for 3-24 hours to prevent hydrogen embrittlement. Critical for aerospace fasteners.

Sealing (Optional)

Additional topcoat sealers can be applied for extreme corrosion environments. Organic sealers fill micro-pores for extra barrier protection.

Final Inspection

Coating thickness measurement, visual inspection, and adhesion testing ensure parts meet specifications.

Available Chromate Finishes

Natural/Clear

Bright metallic appearance

Yellow/Gold Chromate

Gold iridescent finish

Black Chromate

Non-reflective applications

Benefits of Zinc-Nickel Plating

Industry-leading corrosion protection with environmental compliance

Superior Corrosion Resistance

10-15x better than standard zinc plating. Salt spray performance: 1,000+ hours to white rust.

Thermal Stability

Maintains protection up to 300°F. Standard zinc degrades above 140°F.

Excellent Paintability

Chromate-treated surface provides excellent adhesion for paint systems.

Hydrogen Embrittlement Resistance

Lower risk compared to cadmium. Suitable for high-strength steel up to 220 ksi.

Uniform Coating Distribution

Good throwing power means recesses and internal features receive adequate coating.

RoHS Compliant

No cadmium or hexavalent chromium. Meets environmental regulations.

Cadmium Replacement

Comparable or better performance with environmental benefits.

Cost-Effective Protection

Excellent value compared to exotic coatings like PVD or thermal spray.

Industries Served

Zinc-Nickel Plating Solutions Across Industries

Aerospace & Aviation

Automotive

Industrial Equipment

Technical Specifications

Industry standards and material compatibility for zinc-nickel plating

Industry Specifications

ASTM B841

Electrodeposited Coatings of Zinc-Nickel Alloy Deposits

AMS 2417

Plating, Zinc-Nickel Alloy (Aerospace)

ISO 19598

Zinc-Nickel Alloy Coatings (International)

SAE J2329

Electrodeposited Coatings of Zinc-Nickel Alloy (Automotive)

MIL-DTL-81706

Plating, Zinc-Nickel Alloy (Defense)

Typical Coating Thickness

Type I (Thin)

Light duty applications

0.0002"

(5 microns min)

Type II (Standard)

General purpose coating

0.0003"

(8 microns min)

Type III (Heavy)

Severe environment protection

0.0005"

(12 microns min)

Coating Thickness

Carbon Steel

1010, 1018, 1020, A36

Alloy Steel

4140, 4340, 8620

High-Strength Steel

Up to 220 ksi with baking

Cast Iron

With proper pre-treatment

Stainless Steel

Anodic coating accelerates corrosion

Aluminum

Not suitable for zinc-nickel

Copper/Brass

Not suitable for zinc-nickel

Note:

Aluminum, copper, and other non-ferrous metals are not suitable for zinc-nickel plating. Contact us for alternative coating solutions for these materials.

Frequently Asked Questions

Find answers to common questions about Zinc-Nickel Plating services.

How long does hardcoat anodizing take?

Typical lead time is 10-14 business days from when parts arrive at the facility. The actual anodizing process takes 6-8 hours including pre-treatment, anodizing (45-90 minutes), sealing, and inspection. Expedited service available for critical aerospace/defense projects.

What aluminum alloys work best with hardcoat anodizing?

6061, 7075, 2024, and 5052 produce excellent results. 6061 is most common for general applications. 7075 achieves highest hardness. 2024 is standard for aerospace. Casting alloys (356, 380) produce softer, less uniform coatings due to silicon content.

How thick should the hardcoat be?

Depends on application. Light wear: 0.0008"-0.0015". Standard applications: 0.0015"-0.0025". Heavy wear: 0.0025"-0.004". Thicker isn't always better—excessive thickness increases brittleness and cracking risk, especially on edges and corners.

Will hardcoat anodizing change my part dimensions?

Yes. Coating grows approximately 50% inward and 50% outward. For 0.002" coating, expect +0.001" dimensional change per surface (+0.002" on diameter). Critical dimensions should be masked or designed with coating growth in mind. Threads typically masked or chased after anodizing.

Can hardcoat be applied to welded aluminum?

Yes, but with considerations. Weld areas may anodize differently (lighter color) than base material due to different alloy chemistry. Appearance will be non-uniform but functionality (wear, corrosion resistance) is maintained.

Does hardcoat anodizing meet aerospace specifications?

Yes. When performed to MIL-A-8625 Type III or AMS 2469, hardcoat anodizing meets aerospace requirements. Our Nadcap-accredited partners are qualified for aerospace critical applications and provide complete documentation including FAI when required.

Can I get colored hardcoat?

Yes. Black is most common for functional applications. Gray, gold, olive drab, and other colors available. Note: colors are darker/muted compared to Type II anodizing due to coating density and thickness. Natural (undyed) hardcoat is gray.

What is the wear resistance compared to hard chrome?

Hardcoat anodizing (60-70 HRC) is comparable to hard chrome plating (65-70 HRC) in terms of hardness. However, wear performance depends on specific application. Hardcoat excels for abrasion resistance; hard chrome excels for sliding wear.
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