Surfaces & Coatings-ANALYTICS IN THE AREA
Climate and Climate Change Testing
Components can be coated with either metallic or organic materials, such as paints. Often, a material mix is used, for example, where a plastic substrate is refined with a metallic coating or a metallic substrate with an organic paint layer. Different materials exhibit varying behaviors when subjected to cold, heat, or humidity. To prevent optical or technical failures during the later use of the components and parts, we pre-test their behavior under various temperature and humidity conditions.
In climate testing, a defined temperature-humidity profile is performed to the test parts, which they should ideally endure without damage. In some cases, special media, such as harmful gases or corrosive pastes, are added to simulate real-life conditions as authentically as possible. Classic tests include:
Kesternich Test
Testing in Condensation Climates
Climate Change Testing
Corrodkote and Russian Mud
The Kesternich Test uses sulfur dioxide. Sulfur dioxide is produced in combustion engines and is therefore highly relevant for all parts that are "on the move" in road traffic or in industrial halls with operational traffic and corresponding emissions. Due to emissions in road traffic, sulfur dioxide is also partly responsible for acid rain, which means that outdoor components, such as street lamps, railings, or facade parts, are also exposed to it. These are the application cases for the Kesternich Test, which simulates usage-related exposure.
Sulfur dioxide also has the property of uncover heat treatment defects in brass. This is relevant for the sanitary industry, which tests its brass fittings using the Kesternich Test.
Sanitary parts with brass substrates
Engine compartment parts
Wheels, spokes, power unit elements
Facade components
The condensation water climate tests are conducted at a temperature of 40°C and an uncontrolled humidity level between 95% and 100%. The humidity is uncontrolled because it is generated purely through water evaporation. Therefore, during condensation water tests, the test samples are also subjected to dew formation. Testing is done either in a constant climate, where temperature and humidity remain consistent throughout the test period, or in a changing climate, where the chamber is periodically turned off, reducing humidity.
These tests are very informative for organic coatings. Due to the moisture and warm temperature, paints can swell, blister, crack, or chalk.
A special application case for the condensation water constant climate test are hardened steel parts. If there are hardness defects, red rust can form within 100 hours in the test due to carbide precipitations at the grain boundaries.
KTL coatings
Painted parts
Hardened steel parts
In climate change testing, a predefined temperature-humidity profile is automatically performed. Climate change testing is a true all-rounder. It assesses general aging behavior as well as adhesion to the substrate and between single layers.
Every component experiences various climate changes during its later use: indoor and outdoor, summer and winter, extremes such as a car wash. The coating must endure all this without losing its function.
Different materials expand differently. This must be considered in material mixes. For example, if a plastic substrate is metal-coated, the substrate and coating expand differently in heat and contract differently in cold. Under this stress, the coating must neither blister nor crack.
Climate change testing
Temperature shock testing
Heat storage
Cold storage
Special applications require special tests. Even in snowy regions, cars are driven, and to keep roads clear and passable, salt is spread. The residues of snow, salt, and other road dirt accumulate on the vehicle, and in heavy snow, also around the chrome trim or emblems. The acidic, chloride-containing mud is the ultimate enemy for the chrome layer – the chrome is properly eaten away. After a winter, the once beautiful trim elements may no longer look attractive. To prevent this, a synthetic deicing solution is tested beforehand – and because this problem largely occurred in Russia, the associated test is called the Russian Mud Test.
The Corrodkote Test deals with dirt that can deposit on surfaces and either influence them or cause corrosive damage. A dirt-imitating paste is applied, and the test samples are exposed to a condensation climate.
Both tests come in different variations, depending on the part’s intended application in later life.
For enquiries about these analyses, please contact our laboratory team at anfrage@industrial-lab.de or get in touch with your contact person:
Head of Team Corrosion
0212 22147 - 5
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Electroplating technician
0212 2214 - 75
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Head of Laboratory
0212 22147 - 0
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