Tests of Coatings

Adhesion of coating – adhesion testing of coatings on plastic and metal surfaces

Adhesion of coatings is a fundamental quality characteristic for all industrial products where paint, varnish, decorative or protective coatings are applied to plastic or metal surfaces. Inadequate adhesion can lead to aesthetic defects, delamination, blistering or even functional failures, which is why adhesion testing plays a key role in the in-process and final inspection processes. Our laboratory uses standardized procedures to test the adhesion of coatings to provide an accurate picture of the strength of the adhesion between the layer and the base material.

During the test the sample is evaluated under various mechanical loads such as the coating's resistance to pulling, cutting, or peeling under various mechanical stresses. The method is suitable for evaluating both decorative and protective coatings, and is particularly important in automotive, electronics, packaging, and construction applications, where surface quality often directly affects the durability and market acceptance of a product.

Adhesion test results help identify manufacturing defects – such as improper surface preparation, contamination, too thick or too thin coating layers – that are degrading coating performance. Following the diagnosis, we make recommendations to eliminate the causes of the problem, so our customers can optimize their coating technology processes.

Additional special measurements in the coating testing area – such as pencil hardness, scratch resistance, Taber and finger abrasion resistance, chemical resistance, layer thickness, or targeted tests for automotive coatings – all contribute to the complex evaluation of the surface. Adhesion testing is one of the most important of these, as the coating can only perform well in the long term if it is properly bonded to the substrate.

Standard

• MSZ EN ISO 2409
• Volvo VCS 1029,54729
• Volvo VCS 1029,54739
• FORD FLTM BI 106-01
• VW PV 2034
• FIAT 50461

Pencil hardness – evaluation of the scratch resistance of coatings

Pencil hardness testing is one of the most widely used methods for determining the scratch resistance and surface durability of coatings. During the measurement, the resistance of a coating layer is evaluated against various types of mechanical stress, such as marking or minor scratching. The essence of the test is that a pencil of defined shape, size, and hardness is drawn or pushed across the surface of the coating, and then it is observed which hardness level is the highest that does not yet cause damage.

The pencil hardness of the coating corresponds to the hardness of the hardest pencil that still does not leave permanent damage on the surface. This value is an important quality parameter, as it clearly indicates how resistant the coating is to the mechanical effects that occur during everyday use. It is especially significant in industries such as automotive manufacturing, decorative coatings production, surface treatment of electronic products, and the packaging industry, where scratch resistance also determines expected service life and aesthetic quality.

Pencil hardness testing complements other coating tests – such as adhesion tests, scratch resistance testing, or Taber abrasion resistance measurements – thus providing a comprehensive picture of coating performance. The method is fast, cost-effective, reproducible, and based on standards, that is why it is used as a reliable quality control procedure in our laboratory

Standard
FIAT 50452-02
MSZ EN ISO 15184

Abrasion and Resistance to Wear (Finger Abrasion) – Testing the Durability of Coatings

The abrasion and wear resistance test (commonly known as the “finger abrasion test”) is one of the most important quality control procedures for determining the durability of coatings, painted surfaces and pad prints. The method aims to simulate the mechanical stresses that occur in real life when surfaces are subjected to repeated rubbing, touching or cleaning – all of which can cause serious wear or aesthetic deterioration in the long term.

The test is performed using a specially developed finger abrasion device, which allows for precise adjustment of the measurement parameters: the number of cycles, the speed, and the intensity of the fabric or chemical dosage can be controlled. The device performs a repetitive rubbing motion with the help of an artificial finger, which realistically models everyday wear. The test also assesses the surface's resistance to abrasion, changes in coating quality, and paint adhesion.

This test is particularly important in the automotive industry, electronics manufacturing, packaging, and any other industry where surface appearance and durability are important. The results provide an accurate picture of how well a given coating will withstand regular handling, cleaning, or chemical exposure.

Standard
MSZ EN 60068-2-70
Ford FLTM BN 155-01

Resistance to abrasion (Taber) – surface durability testing using the rotating disk method

The Taber abrasion and resistance to abrasion test is one of the most reliable methods for determining the surface resistance of various materials. The purpose of the measurement is to accurately assess how well coatings, fabrics, rubber mats, leathers, as well as floor and luggage compartment coverings can withstand long-term mechanical stress.

The test is performed using a rotating disk abrasion resistance device, where the surface of the sample is abraded under a defined pressure using standardized abrasive wheels. The test simulates real-world conditions, so it can be accurately demonstrated how the texture, gloss or structural integrity of the surface changes under long-term stress. The method is particularly important in the quality control of automotive interior elements, luggage compartment coverings, floor coverings, as well as household and industrial materials.

Taber test results provide a reliable indication of a product’s expected life, wear resistance, and whether a given material meets manufacturer or industry specifications. This allows manufacturers to minimize complaints, optimize surface preparation processes, and ensure consistent quality.

Standard
MSZ EN ISO 7784-2
ASTM D 4060-25
Ford FLTM BN 108-02
SAE J365
SAE J948

For painted plastic automotive parts, it is important that the coating maintains its aesthetic and functional properties over the long term. The interior and exterior of the vehicle are constantly exposed to heat, light, mechanical and chemical stress, so surface quality control is essential at every stage of the production process. The aim of our tests is to accurately determine the durability, stability and behavior of coatings under different conditions.

We test the properties of coatings applied to metallic or non-metallic materials using various processes using some major automotive standards. During the measurements, we evaluate, among other things, adhesion, scratch resistance, abrasion resistance, chemical resistance, resistance to environmental influences and coating integrity. These results support quality control, OEM approval processes and help to detect and prevent manufacturing defects.

The test is closely related to other coating test areas – such as adhesion, pencil hardness, abrasion and wear resistance, scratch resistance, moisture resistance or coating thickness – which are presented in detail in separate submenus.

Applied automotive standards

Properties of painted and lacquer-coated plastic automotive components

• Daimler DBL 9202

• VW TL 226

• Ford WSS-M2P188-B1

• Fiat 9.55842/01

The purpose of the cylindrical mandrel bending test is to determine the resistance of painted or coated surfaces to mechanical stress. During the test, the sample is bent over a cylindrical mandrel of a specified diameter, while the behavior of the coating is monitored under constant, controlled conditions. This method is particularly suitable for determining the ability of the coating to follow the deformation of the base material without cracking, delamination or other surface damage.

A test in which the resistance and behavior of the paint/coating formed on a metal surface is determined by bending the sample over a cylindrical mandrel under constant conditions. The results obtained provide important information about the flexibility, adhesion and durability of the coating, which is especially critical in automotive, electronic and construction applications.

The test results help to optimize manufacturing processes, develop coating systems, and verify the compliance of coatings according to various industry standards.

Standard

• MSZ EN ISO 1519

The purpose of testing resistance to scratch is to determine how resistant a given coating or material is to mechanical stress during everyday use. The test is applied to both painted and unpainted parts, thus providing an accurate picture of how sensitive the given surface is to scratching or surface damage.

During the test, the surface is scratched with a specified force and a given geometric design – sharp or blunt – with a test head and we observe how the coating reacts to the load. The method is particularly important in the automotive industry, the electronics industry, and in all areas where the aesthetic and functional integrity of the surface is a critical requirement.

The results obtained help in the development of coating systems, the optimization of the choice of raw materials, and the fine-tuning of manufacturing processes so that the parts maintain their surface quality in the long term.

Standard

• Ford FLTM BN 162-01

• Volvo STD 423-0030

• Volvo STD 1024,3113

• VW PV 3952