Processing effects on the structure and fatigue performance of nickel-based superalloys

ickel-based superalloys exhibit excellent high-temperature mechanical performance and corrosion resistance that enables their use in extremely demanding applications, especially in energy conversion/production where higher operating temperatures lead to enhanced efficiency. Processing techniques that enable the production of tailored microstructures have been a key driver in advancing the performance and expanding the use of these materials. Additive manufacturing (AM) offers a relatively new route for processing superalloys with the possibility of enabling unique microstructure, spatial control and variation of structure and composition, and the production of parts with high geometric complexity.
This project will involve detailed microstructural and mechanical characterisation of nickel-based superalloys that have been processed using both traditional metallurgical processing (e.g. powder metallurgy) and AM techniques. The effect of AM processing parameters will be assessed and compared with the structure, properties, and performance obtained from other processing routes. The fatigue and oxidation performance, including early stage crack initiation processes and subsequent crack propagation, will be characterised and correlated with structural features such as grain size, orientation, and precipitate distribution. The results will be used to benchmark AM against established processing techniques, and to develop and assess strategies for enhanced performance through spatial control and variation of material structure and composition. These efforts will help establish new processes and will inform broader efforts to enhance the future performance of turbines, heat exchangers, and other critical components in energy, transport, and industrial chemical sectors.