Steinbeis experts map global corrosion conditions for metal components
The performance and longevity of any material or technical system exposed to the outdoor elements are influenced in a variety of ways by local environmental conditions. Atmospheric conditions, i.e. the weather and climate, have a particularly strong impact and are often crucial for materials. Any information on conditions is thus of major interest to producers and the actual users of materials and systems. For example, materials can be adapted to specific applications and locations, or maintenance schedules can be optimized. This can significantly improve the economic viability and safety of machinery. This is also important because digital technology and networking within industry mean that development methods and production will become increasingly customized in the future. FeLis, the Steinbeis Research Center specialized in remote sensing data and terrain data systems, is currently working on a research project aimed at modeling corrosion patterns.
An important example that highlights the potential negative impact of atmospheric influences on materials is metal corrosion, which causes significant economic damage year after year. There are a number of scales that show the extent of damage caused by corrosion, and these indicate that damage varies strongly depending on the location. A longterm measurement program would be required to estimate the exact extent of damage by specific location, but for practical reasons this would only be feasible for a small selection of areas, especially given the global nature of material distribution.
To address this issue, the FeLis Steinbeis Transfer Center, based in Bruckberg in Bavaria, has embarked on a collaboration with the Fraunhofer Institute for Solar Energy Systems ISE to develop a comprehensive global mapping system to capture the atmospheric factors that shape corrosion processes. These are mean annual air temperature, mean annual relative humidity, and the mean daily deposition rate of sulfur dioxide and chloride ions. Using these factors makes it possible to draw on dose-effect functions affecting corrosiveness as defined under ISO standard 9223. To develop sets of data on which to base calculations, meteorological information has to be re-analyzed. This information includes past sets of long-term data, which has to be consistent over time and can provide worldwide coverage.
Despite limitations in terms of the available methodologies, such as limited geographical definition due to the global scale of the project or uncertainties regarding the applied standard, the results do make it possible to make a broad-scale assessment of the average risk of corrosion. This includes corrosion rates during the first year of exposure for four metals: copper, zinc, unalloyed steel, and aluminum. One example of a possible application is the assessment of possible long-term damage caused to photovoltaic systems. As such, the data can be integrated into existing systems and databases, or displayed in the form of images to support the decision-making of producers and their customers.