Zinc-Nickel

Capability

Zinc-Nickel Plating

Zinc-nickel plating combines zinc with 12 to 15% nickel in a single deposited alloy that protects steel components in environments where pure zinc isn't enough. The result is roughly five times the corrosion resistance of zinc, with measurably better abrasion resistance and excellent covering power into deep recesses, threads, and complex geometry.

It's the standard finish for severe-duty under-vehicle hardware across the major automotive, commercial vehicle, and off-highway equipment programs, where 1,000+ hours of ASTM B117 salt-spray performance to red rust is the baseline expectation.

Salt-Spray Performance

1,000+ hrs

ASTM B117 to red rust, 5× zinc

Nickel Content

12–15%

Within the deposited alloy

Typical Thickness

8–15 µm

0.0003" to 0.0006" per spec

Processing

Rack & Barrel

Willow Run built for rack zinc-nickel

Two Plating Chemistries

Alkaline and Acid Zinc-Nickel Systems

CMC runs both alkaline (non-cyanide) and acid (chloride) zinc-nickel plating chemistries. The right system for a given program depends on the substrate, the part geometry, post-plate forming requirements, and the throughput target.

Alkaline (Non-Cyanide)

Uniform thickness, complex geometry

Alkaline zinc-nickel systems produce uniform plating thickness across complex geometry, recesses, and threaded fasteners. They operate at 30 to 50% efficiency and support two nickel content ranges: a 2 to 5% alloy and a 12 to 16% alloy. Best fit for tubular components, complex stampings, and parts that undergo post-plate forming.

Acid (Chloride)

Faster deposition, cast-iron friendly

Acid zinc-nickel systems deposit roughly twice as fast as alkaline at higher overall efficiency, producing alloys with 10 to 15% nickel content. Best fit for cast iron substrates and simpler stamping geometries where deposition speed and substrate chemistry favor an acid bath.

Where Zinc-Nickel Fits

Common Applications

Zinc-nickel is the go-to finish when severe-duty corrosion performance, abrasion resistance, and threaded-component reliability all matter on the same part.

  • Brake lines and fuel lines — tubular components that need 1,000+ hr corrosion life under-vehicle
  • Fasteners — high-strength bolts and nuts (Class 10.9, 12.9) where corrosion and hydrogen embrittlement both need to be controlled
  • Brake calipers and knuckles — cast iron components where the acid system performs well
  • Chassis hardware — suspension components, subframe fasteners, under-vehicle brackets
  • Engine compartment hardware — fasteners and brackets that face heat, chemicals, and corrosion together

Substrate Range

Steel, Cast Iron, and High-Strength Alloys

Zinc-nickel plates cleanly across the range of substrates the automotive and heavy-equipment supply chains run: ordinary carbon steel, high-strength low-alloy steel, Class 10.9 and 12.9 fastener stock, and cast iron components like brake calipers and knuckles.

For high-strength steel components, CMC performs in-house hydrogen embrittlement relief baking within the time windows ASTM F1940 and major OEM specifications require, ensuring critical fasteners and structural parts are protected from delayed brittle failure after plating.

Color & Performance

Passivate and Topcoat Options

After plating, zinc-nickel parts receive a passivate layer that boosts corrosion resistance and gives the part its final color. CMC runs clear, black, and yellow passivate variants — all in trivalent chromium chemistry, fully hexavalent-chromium-free, and meeting RoHS, REACH, and end-of-life vehicle directives.

For the most demanding applications, an additional topcoat/seal can be applied over the passivate, adding a final layer of corrosion protection and friction control. The combination of zinc-nickel plating, trivalent passivate, and topcoat is what carries hardware through the 1,000+ hour salt-spray specifications that modern automotive and commercial vehicle OEMs publish.

Production Capabilities

Purpose-Built for Rack Zinc-Nickel

Across our four facilities and 17 processing lines, zinc-nickel plating is available in both rack and barrel processing methods. Marsh Plating Willow Run — opened in 2016 specifically to expand the group's rack capacity — was purpose-built around rack zinc-nickel and rack electroless nickel for fasteners, brake components, and the structural hardware that modern automotive and heavy-duty programs depend on.

Every line is fully automated, with chemical feed systems on most process tanks running on automated control. The result is consistent finishing across high volumes, with IATF 16949 process control aligned to the automotive supply chain requirements every program lives by.

Who Specifies Zinc-Nickel

Industries We Plate For

Zinc-nickel is the specified finish across most modern severe-duty programs. CMC plates zinc-nickel for customers in:

Specifications & Standards

Standards We Can Meet

ASTM B841

Standard specification for electrodeposited coatings of zinc-nickel alloy

ASTM B117

Salt-spray testing, 1,000+ hr to red rust on 12–15% nickel zinc-nickel

ASTM F1940

Hydrogen embrittlement relief baking, performed in-house

GMW3044 / GMW14872

GM zinc-nickel and cyclic-corrosion specifications

Ford WSS-M21P39-A2

Ford zinc-nickel specification for under-vehicle hardware

IATF 16949

Automotive quality management process control across all facilities

RoHS, REACH, ELV

Trivalent chromium passivation, fully hexavalent-chromium-free

Specifying zinc-nickel for a part?

Send us a drawing, an OEM specification, or a part description. We’ll match the right zinc-nickel chemistry (alkaline or acid), the right passivate, and the right processing method to your substrate, your geometry, and the standard your program runs to.