Dorken Coatings

Zinc Flake Coatings From Dörken Coatings: Ultra-Thin And Highly Reliable Protection Against Corrosion

From small nuts and bolts to large steel components: suitable corrosion protection must be considered for every metallic component right from the planning stage. Electrochemical reactions alter the properties of the metal and can considerably impair its functionality. Cathodic corrosion protection is a reliable solution in which a zinc flake coating acts as a barrier. In the event of a corrosion attack, the zinc sacrifices itself due to the low electrochemical potential thus protecting the steel component.

You can count on the expertise and experience of Europe’s market leader in microlayer corrosion protection systems: A zinc flake system from Dörken Coatings meets all complex requirements.

Since Dörken Coatings developed its first application of zinc flake coating in 1989, continuous further development and innovation have made us the reliable partner for corrosion protection with efficient zinc flake coatings.

How Is A Zinc Flake System Created?

A zinc flake coating is a modular system consisting of a basecoat and a topcoat. The individual components can be combined to precisely satisfy characteristic requirements (specific coefficient of friction, chemical resistances etc).

Corrosion Protection Basecoat: The basecoat is the zinc flake coating and is applied directly to the substrate to be treated. This base layer determines the corrosion protection properties. The zinc content provides a high level of cathodic corrosion protection. For bulk materials, such as thread-rolling screws, application by dip spin process is typical, for larger components the spraying process (manual or by robots) is recommended.

Corrosion Protection Topcoat: The topcoat complements the properties of the basecoat, and gives the coating additional multifunctional properties. In addition to corrosion protection, the topcoat protects against chemical and mechanical impacts and is responsible for the:

• Requirements of coefficient of friction
• media resistance
• weathering resistance
• appearance
• and other individual requirements

What Are The Benefits Of A Zinc Flake System?

For more than 30 years, zinc flake coatings have been used in the automotive industry, among others, but the strengths of this coating are also increasingly being used for construction machines and in the field of renewable energy.

An overview of the main advantages of zinc flake coatings: 

• Cathodic protection: The zinc flake coating functions as a metallic layer consisting of many small flakes. In most cases they consist of a combination of zinc and aluminium flakes bound together through an inorganic matrix. Since the sacrificial effect of zinc actively protects the component from environmental and chemical influences, the zinc flake coating offers a high level of cathodic protection.
• Low layer thickness: The total layer thickness of the coating is on average only 8-20 µm and is therefore thinner than a human hair. Compared to other corrosion protection systems such as powder coatings or hot-dip galvanizing, the zinc flake coating is almost invisible, but nevertheless achieves a protective effect of over 1,000 hours against base metal corrosion in the neutral salt spray test in accordance with ISO 9227.
• High accuracy of fit: Reliable corrosion protection with a very thin texture: Zinc flake systems are ideal for components whose standards place high demands on fitting accuracy, for example, screws with metric threads.
• No stress corrosion cracking: With zinc flake coating, no hydrogen is provided during the application process, which prevents application-related, hydrogen-induced stress corrosion cracking. Zinc flake systems are therefore the best choice for high-strength steels (Classes 10.9 and higher).
• Attractive appearance: It is possible to adapt the visual appearance of the zinc flake coating to customer requirements through the selection of the topcoat. By overpainting with a paint that does not damage the corrosion protection of the zinc flakes, different colour variations are also possible, for example, for marking different components.

Not Just Zinc Flake Coating... Dörken Coatings Offers The Right Coating Solution For Every Application.

The choice of the suitable process for corrosion protection always depends on your individual requirements. As an expert in corrosion and surface protection, Dörken Coatings offers other proven processes in addition to zinc flake systems, such as:

• Electroplating
• Cathodic dip coating (KTL)
• Coil coating

Visit https://www.doerkenusa.com/us