"New generation of NiAl-based eutectic composites with tuneable properties"
Ni-based superalloys have been state-of-the-art material for aeroengine applications due to their excellent creep strength, oxidation resistance, and fracture toughness. However, nickel-base superalloys are approaching one fundamental limitation – their melting point. Some of them are already operating at temperatures of 90% of the melting point. Hence, in order to achieve service temperatures higher than those of nickel-base superalloys, materials with significantly higher melting points are required. Intermetallics have been recognized as perspective substitutes for some of the Ni-based superalloys. A B2-ordered intermetallic compound NiAl and its alloys have attracted a particular interest of the scientific community, as they offer several advantages over the currently used nickel-based superalloys including a higher melting point (1,674°C), a significantly lower density (5.86 g/cm3), distinctly higher thermal conductivity (76 W/mK) as well as excellent oxidation resistance at high temperatures
The major objective of the project is to design and develop new generation of multiphase intermetallic alloys based on NiAl. In contrast to contemporary concepts of alloy design, a novel high-throughput method for systematic microstructure investigation and control will be presented. In addition, the use of pseudo-binary eutectic trough concept will be presented for the first time to the scientific community. It will enable the gradual change of the volume fraction of the reinforcement phase, and thus adjustment the properties of the alloys. The greatest challenge, however, will be to obtain a single alloy with high strength and fracture toughness, good ductility and formability, as well as sufficient thermal stability and oxidation resistance.
Funding Organization: Marie Curie Action-CIG, 7th Framework Programme
Project Period: 2012 – 2016
Principal Investigator: Dr. Srdjan Milenkovic