DACROMET® Coating

For more than 35 years, DACROMET® has been used worldwide for high performance corrosion protection on wide variety of metallic parts
Thin dry-film, non-electrolytic, self-lubricated or not
Water-based chemistry
Passivated zinc and aluminium flakes in a binder, patented chemistry
Binder contains chromium oxide (Cr3+ and Cr6+)
Metallic silver appearance

What is DACROMET®

DACROMET® is an aqueous solution comprising zinc in flake phase, aluminium metal powder and inorganic compound. It is normally treated by dip and spin coating of this aqueous solution followed by heat-treatment at a relatively high, that is, about 300°C temperature. As a result, 7-8 μm thick coating is formed by drying and curing during the hot air drying process. Metal zinc and aluminium, which constitute the coated film, can protect steel via self-sacrificing, namely, by inhibiting the corrosion of a given steel due to the electric activity of highly ionisable metal zinc. Here, the chromic acid in a polymerized state can control and inhibit the self-sacrificing of metal zinc thus serving the role of a binder while also establishing the passivation of coating, which then leads to inhibition of chemical reaction between zinc and iron and accordingly reduces the speed of corrosive progress, thus exhibiting high corrosion resistance. In addition, the zinc, aluminium flake and metal oxide, which are of multi-layered structures, can protect the surface of iron alternatively thus functioning as a barrier against external corrosive factors thereby exhibiting superiority in corrosion resistance.

Characteristics and Performance*
• Controlled coefficient of friction (ISO 16047):
• DACROMET® 320 + PLUS® or DACROLUB® topcoat ⇒ μ from 0.06 to 0.19
• DACROMET® 500 ⇒ μ = 0.15 ± 0.03 without topcoat
• No hydrogen embrittlement
• Excellent assembly and multi-tightening behaviour (with lubricated topcoat)
• Good mechanical damage resistance (trial method D24 1312, USCAR 32) and chemical resistance (trial VDA 621-412)
• Suitable for high-temperature applications (up to 300°C)
• Paintable coating
• Electrical conductivity for most application processes
• Competitive application costs
• Bimetallic compatibility with aluminium

* Results may vary depending on substrate, geometry of parts and type of application processes
Application Process
DACROMET® can be applied by Dip-Spin, Spray or Dip-Drain (Spin) using bulk or rack

Health and Safety
• Aqueous dispersion
• Complies with REACH

National & International Standards
• EN ISO 10683 – Fasteners: non-electrolytical zinc-flake coatings
• EN 13858 – Non-electrolytical zinc-flake coatings on iron or steel parts
• ASTM F1136 / F1136 M – Zinc/Aluminium corrosion protective coating for Fasteners