Science predicts durability timelines for materials exposed to solar radiation
Explore the ScienceSunlight is not only a source of life and warmth but also a powerful factor in material degradation. Under its influence, automotive polymer parts lose strength, paint coatings fade, and even cut flowers wilt quickly. Predicting product durability under solar radiation is a complex scientific task combining materials science, climatology, and mathematical modeling.
Solar radiation, especially its ultraviolet component (UV radiation), initiates complex physical-chemical processes on the surface and within materials.
The thermal state of a product, formed under solar radiation and heat exchange with the environment, is crucial. Mathematical modeling of non-stationary thermal state allows predicting the equivalent operating temperature—the constant temperature that would cause the same level of material degradation as real changing conditions 1 .
One of the most authoritative centers for studying climate impact on materials is the Gelendzhik Center for Climate Testing named after G.V. Akimov (GCKI VIAM).
Annual solar radiation dose
Average air humidity
Corrosion category for steel
Steel plates undergo abrasive blasting (Sa 2.5 according to ISO 8501-1) to ensure adhesion. A coating system is applied: zinc-rich primer, intermediate, and finish enamel layers with total thickness of 150-200 μm 7 .
Samples are placed on atmospheric stands at a 45° angle to the horizon, 20 meters from the water's edge, ensuring exposure to both solar radiation and sea salts 7 .
Using a meteorological complex (16 atmospheric parameter sensors) and hydrological complex (15 water parameters), continuous measurements are taken of solar radiation intensity, air temperature and humidity, wind speed and direction, sample surface temperature, and chloride concentration in the air 4 .
At specific intervals, samples undergo visual inspection and instrumental measurements: color change (CIELAB system), chalking appearance (ISO 4628-6), rust appearance (ISO 4628-3), blistering (ISO 4628-2), and adhesion loss (ISO 4624) 7 .
| Location | Climate Zone | Radiation Dose (MJ/m²) | Corrosion Category |
|---|---|---|---|
| Gelendzhik Center | Moderately Warm | 4956 | C3 (Medium) |
| Tropical Station | Tropical | ~5500 | C5 (Very High) |
| Temperate Station | Temperate | ~3500 | C2 (Low) |
| Atmosphere Type | Color Change, ΔE | Chalking | Rust | Adhesion, MPa |
|---|---|---|---|---|
| Marine (Gelendzhik) | 3.2 | 1 | 0 | 4.5 |
| Industrial | 5.8 | 2 | 1 | 3.8 |
| Rural (Clean) | 2.1 | 0 | 0 | 4.9 |
A combination of methods—from field testing to accelerated laboratory tests and mathematical modeling—is used to predict durability timelines.
Perm Polytechnic University developed the TeSunRad algorithm and program for calculating non-stationary thermal state of complex-shaped products considering solar radiation. The method is based on the variational formulation of the heat conduction problem and its implementation through the finite element method (FEM) 1 .
To reduce research time, artificial climate chambers are widely used, reproducing the effects of solar radiation, temperature, and humidity in an accelerated mode.
| Research Method | Reproduced Factors | Advantages | Disadvantages |
|---|---|---|---|
| Field Testing | Full range of natural factors | Maximum reliability | Long duration (years) |
| Cyclic Testing | Temperature, humidity, UV, SO₂, salt fog | Factor combination | Weak correlation for some materials |
| UV Chamber Testing | UV radiation, temperature, humidity | Speed, controlled conditions | Simplified simulation |
Durability prediction finds applications across diverse industries, enabling better product design and maintenance strategies.
Calculation of equivalent operating temperatures helps predict the service life of polymer materials in machines and structures operating in natural conditions 1 . This is critical for ensuring safety and reliability.
Evaluation of coating weather resistance helps select optimal protection for structures in various climates—from seacoasts to industrial areas 7 .
Sunlight accelerates wilting of cut flowers. Integrating weather data into accounting systems allows predicting shelf life of different flower varieties, optimizing purchases and logistics, and reducing spoilage losses 3 .
Predicting product durability under solar radiation has transformed from art to science. Modern mathematical modeling methods combined with field and accelerated testing allow highly accurate predictions of material behavior in real operating conditions.
Accounting for factor synergy
Expanded testing network
Improved testing chambers
Business process optimization