High performance ‘superalloys’ are metal composites made of two or more elements that exhibit superior properties and performance during prolonged exposure to very high temperatures. They are widely used in jet engine turbine blades that are subjected to the most extreme conditions within the engine. For this application, the main alloy component is often nickel (Ni). European researchers designed the ‘Ultra high temperature materials for turbines’ (Ultmat) project to investigate new molybdenum (Mo)- and niobium (Nb)-silicide–based alloys with improved high temperature capabilities compared to standard Ni-based superalloys for the production of aircraft/rotorcraft engines as well as land-based gas turbines. The project researchers first developed and characterised a number of alloy compositions to determine the ones that best fulfilled specifications. They sought materials that could successfully operate at temperatures 100–150 degrees Celsius higher than the current Ni-based alloys while providing good ductility, mechanical strength, creep resistance (resistance to deformation under sustained loads at elevated temperatures) and oxidation resistance. In addition, given that the key to commercialisation is feasibility of large-scale manufacturing, Ultmat partners produced large quantities of the selected materials using standard industrial procedures and equipment thus validating the materials’ industrial usefulness. The Mo-silicide–based alloys demonstrated satisfactory mechanical properties and oxidation resistance, whereas the Nb-silicide–based alloys demonstrated excellent creep resistance. The researchers also investigated coatings and deposition techniques for the Nb-silicide–based alloys that enhanced temperature resistance of turbine components in the range above 800 degrees Celsius. Furthermore, they created a database of physical, thermal and mechanical properties of the alloys relevant to application in gas turbine hot sections. The Ultmat project successfully contributed to a precise characterisation and understanding of the promises and limitations of Mo- and Nb-silicide–based alloys for the production of turbine components subjected to very high temperatures. The study outcomes offer potential for future development of turbine components based on these materials, which will result in reduced fuel consumption and CO2 emissions with increased efficiency. Advances in this area will enhance European competitiveness in the high performance materials market while providing cost and environmental benefits to European consumers.