Discover our accelerated UV weathering tests for durability control
Understanding photo-degradation
Sunlight exposure can lead to colour and gloss changes, significantly altering the appearance and performance of coatings, paints and other polymer-based materials.
Depending on their composition, polymers are more or less sensitive to solar radiation, and long-term exposure can provoke surface modifications, paint peeling, or even micro-cracking after extended ageing.
Beyond sunlight alone, temperature and humidity play an essential role in degradation mechanisms, alongside other natural factors such as wind, rain, sand or hail.
The impact of UV radiation
The ultraviolet part of solar radiation (especially UVA and UVB) contains enough energy to break chemical bonds in polymer networks, initiating free radical reactions that lead to degradation.
These reactions can involve photo-oxidation, thermal oxidation or hydrolysis, ultimately modifying several material properties:
Colour and gloss variations
Increased water permeability
Reduced mechanical resistance
Accelerated coating failure
Accelerated ageing at CRM Group
To reproduce and study these effects under controlled conditions, CRM Group mostly operates two complementary accelerated UV weathering systems:
- QUV tester → principally with UVA lamps to simulates the UVA range of sunlight (<365 nm)
- Xenon tester (QSUN) → reproduces most of the solar spectrum
These devices make it possible to control and combine the three main degradation parameters, light, temperature and humidity, to assess material durability and compare formulations.
Sample configurations
While primarily designed for flat samples of limited thickness, CRM Group has developed adapted supports enabling tests on specimens with relief up to 20 mm in QUV.
Typical sample sizes are:
- QUV: 75 × 150 mm
- QSUN: 51 × 102 mm (other holders available)
Other holders are available to accommodate different sizes.
Extensive testing capability in Europe
With one of the largest QUV testing facilities in Europe, CRM Group supports clients from various industrial sectors, construction, automotive and general industry, in evaluating and improving the durability and UV resistance of their products.
These accelerated ageing tests provide reliable data to predict long-term behaviour, support product qualification, and guide material selection for demanding environments.
Just send an email to to meet our experts and learn more about our UV weathering and durability testing capabilities.
