The Coating Portfolio

Zinc Flake Coating Services — GEOMET®, Top Coats & More

From GEOMET® zinc flake to PTFE fluoropolymers — explore the full Aum Dacro range, the products within each system, and how they compare. Pick a product to see its specs come alive.

5Coating families
40+Product systems
2000hMax salt-spray
Cr-freeChemistry
Coating cross-sectionBUILD
SUBSTRATE › BASECOAT › TOPCOAT Steel substrate
Film 0 µmLayers building…
Family 01 · Flagship

Zinc Flake Coatings

Advanced, non-electrolytic anticorrosion systems built from overlapping zinc–aluminium lamellae. They deliver a thin, uniform barrier without altering dimensions — and their defining advantage is no hydrogen embrittlement, making them the trusted choice for high-strength fasteners.

Superior corrosion resistance (1000–2000 h SST)
Thin coating thickness (5–20 µm)
No risk of hydrogen embrittlement
Heat resistance up to 300 °C
Eco-friendly, RoHS / REACH compliant
Excellent adhesion for topcoats & lubricants
Family 02 · Friction Control

Top Coats

Multifunctional sealers applied over a zinc flake basecoat. They stabilise the coefficient of friction, add chemical resistance and colour, and boost overall corrosion performance. Select a product to see its friction window.

Torquer Series · Anti-Loosening

Stabilising the coefficient of friction delivers a consistent clamp load — preventing loosening while cutting cost and weight.

01

Stable axial force

A stable friction coefficient yields consistent clamp load across every bolt at the same torque.

02

Consistent friction

Reduces friction-coefficient variation — three line-ups let you match the exact requirement.

03

Maximise bolt use

At 20 N·m on M8, output rises from ~7 kN (dry) to ~17 kN — far more from the same bolt.

04

Fewer, smaller bolts

More clamp force means fewer and smaller fasteners — reducing cost and total weight.

Family 03 · Diffusion Alloy

Zinc Thermal Diffusion

A high-temperature diffusion process forms a zinc–iron alloy directly on the metal surface — a metallurgically bonded coating that will not flake, chip or peel, even under extreme conditions. Completely dry and eco-friendly, with no liquid baths or chemical waste. Proven by brands like ArmorGalv® (Distek).

  • Exceptional corrosion resistance
  • Uniform, chip-free zinc–iron alloy coating
  • Environmentally friendly — no liquid effluents
  • Excellent wear & abrasion protection
  • Ideal for complex geometries & threaded parts

Thermal Zinc Diffusion (TZD)

3000+ h

Corrosion resistance with a uniform, chip-proof, metallurgically bonded zinc–iron layer — including full coverage on threads and internal surfaces, via a dry, eco-friendly process.

Family 04 · Electrolytic

Electroplating

Depositing a thin metal layer using electric current to improve corrosion resistance, aesthetics and electrical conductivity — with exceptional throwing power on complex parts.

Family 05 · Fluoropolymer

PTFE Coatings

High-performance fluoropolymer coatings known for exceptional non-stick properties, chemical resistance and low friction — used across automotive, aerospace, food processing, medical and industrial manufacturing.

Superior non-stick properties
Extreme temperature resistance
Excellent chemical resistance
Low friction & lubrication
Corrosion & moisture resistance
Electrical insulation
Legacy Systems

DACROMET® vs GEOMET® — understanding the upgrade path

DACROMET® is the earlier-generation zinc flake coating from the same technology family. It contains hexavalent chromium (Cr VI), which restricts its use in EU ELV, RoHS and REACH-regulated assemblies. GEOMET® is the chrome-free successor — same cathodic protection, no restricted substance. If your drawing still calls out DACROMET®, we can advise on the GEOMET® equivalent and manage the qualification.

Compare the systems

Which coating fits your part?

Zinc FlakePTFEZinc ThermalAlkaline ZincAlkaline Zn-NiHot-Dip Galv.
ApplicationNon-electrolytic (dip-spin / spray)Spraying / coatingThermal diffusionElectroplatingElectroplatingMolten-zinc immersion
Corrosion protectionExcellent (cathodic + barrier)Good–excellent (barrier)Very good–excellent (cathodic + barrier)Good (cathodic)Superior (cathodic)Excellent (cathodic + barrier)
Thickness (µm)Thin (5–15)Varies greatlyThick (50–500)Thin (5–20)Thin (5–15)Thick (45–200)
Unique strengthNo hydrogen embrittlement — ideal for high-strength fastenersExtremely low friction (non-stick) & chemical resistanceCoats large structures & complex threads with a bonded layerExceptional throwing power on complex partsHighest corrosion resistance of plated coatings (>1000 h)Metallurgical bond; most cost-effective for structural steel

Not sure which coating your part needs?

Send us your drawings or specs — our technical team recommends the right system within one business day.

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Reference

Zinc flake coating FAQs

What is zinc flake coating?

A non-electrolytic coating of overlapping zinc and aluminium flakes in an inorganic binder, applied by dip-spin or spray and cured. It provides cathodic corrosion protection without hydrogen embrittlement risk, in a film thin enough to preserve fastener thread fit.

Zinc flake vs zinc plating — which is better?

For high-tensile fasteners, zinc flake avoids hydrogen embrittlement and reaches higher salt-spray life at lower thickness. Zinc plating remains preferable where conductivity, a bright finish or lowest cost per part is the priority.

How thick is a zinc flake coating?

Typically 8–12 µm for basecoat, rising to 10–20 µm with a top coat. Thin enough to preserve thread fit on fasteners, which is a key advantage over hot-dip galvanising.

Does zinc flake coating contain hexavalent chromium?

No. GEOMET® and the zinc flake systems we apply are Cr(VI)-free, which allows use in assemblies subject to EU ELV, RoHS and REACH.

What salt spray hours does zinc flake achieve?

Performance depends on the system, film build and part geometry. Zinc flake basecoat-plus-topcoat combinations are commonly specified for several hundred hours to red rust under ISO 9227, with higher-performing systems available.

What is the difference between GEOMET® and DACROMET®?

Both are zinc flake systems. DACROMET® is the older generation containing hexavalent chromium; GEOMET® is the Cr(VI)-free successor. For regulated assemblies, GEOMET® is the correct specification.