Ceramics and Coating Technologies
(Prof. Dr. rern. nat. Robert Vaßen)
The aim of this lecture is to familiarize advanced students from engineering and science fields with application-relevant knowledge that they need to understand processing, properties and life limiting processes of ceramic structural materials and components. While traditional ceramic (used in all households as stoneware, porcelain, etc.) is not subjected to severe service conditions, synthetically produced, dense and high-strength structural or engineering ceramics (for example aluminum oxide, silicon carbide, etc.) are heavy-duty construction materials. There are cases where they even outperform metals, especially in working environments where resistance against corrosion attack and wear is required in combination with high-temperature stability and low density. Scale bridging material science characterizes today’s ceramic research. It is important to understand the atomic structure of ceramic materials and to appreciate the steps required to process high-performance oxidic and non-oxidic ceramic components. Standard characterization and testing methods also receive due attention, with special emphasis placed on how materials data can be used for design. Base materials are coated to improve properties (like thermal isolation potential), to extend the application range (e.g. to higher temperatures) or to prolong the exploitable service life. A technical coating can combine various protective functions. It can enhance the corrosion resistance. At the same time, it can contribute to a better resistance against erosion and other types of wear loading. It can act as a thermal isolator and thus contribute to a decrease of thermal stresses. Typical examples of coatings and coated systems are presented together with their processing routes. These include methods based on physical and chemical vapor deposition (PVD and CVD) as well as thermal spray processes (flame, plasma, arc spraying, etc.) and other methods (electrolytic deposition, immersion procedures and overlay welding).
The class is organized as a lecture block in the winter semester and will be announced in due time.