Sunlight, heat, and water induce ageing processes in any material – called weather ageing, environmental ageing, or just “weathering”. Irreversible chemical and physical changes first appear on microscopic level and accumulate over time into unwanted macroscopic changes, e.g. discoloration, yellowing, flaking, or loss of tensile strength. If a critical property exceeds a certain “pass-fail” criterium, the end of service life is reached.
Environmental ageing cannot be avoided. But service life can be significantly extended by
- proper product design,
- choice of most suitable materials, and
- state-of-the art chemical and physical stabilization.
Relative and Absolute Approach in Accelerated Testing
Applying accelerated weathering tests according to industry-accepted testing standards helps to compare product durability to known reference materials or a given pass-fail criterium. This is called the “relative approach”. The “absolute” aproach is to determine or estimate the actual service lifetime in specific end-use conditions.
Prediction ist Very Difficult, Especially if it’s About the Future
This quote is from Danish physicist Niels Bohr. He does not say “it is impossible”.
During the last years, weathering scientists have developed a toolbox of methods, models, formulas, and approaches to tackle the challenge of service life prediction – or “SLP”. Chosing the right tools and models is critical for any attempt to predict - or better estimate – service life.
A brand-new seminar presents the basic concepts you should know about SLP: models, formulas, approaches, and limitations. Check out when the seminar is presented next in our seminar calendar or listen to the recorded online seminar on SLP.
More Information
Just recently, on June 28, Atlas presented on uncertainty budget of service life prediction models
based on accelerated weathering at the 2023 ASTM G03 Workshop on Weathering and Durability Testing. We are planning to publish a similar online seminar or even a White Paper on this topic in the future. Do not miss it and subscribe to the Atlas Weathering Blog with your email address.
For more information, browse our Knowledge Center.