"Computational and experimental design and development of advanced NiAl-based in situ composites with tunable properties"
Structural metallic materials for applications in turbine blades are attractive not only from industrial, but also from environmental and socio-economical standpoints. The Ni-based superalloys have been the state of the art materials for high temperature services. Nevertheless, ever increasing working temperatures of the components need further alloy development. On the other hand, intermetallic compounds have been considered as promising candidates to substitute some of the Ni-based superalloys. Among a large number of the intermetallics with attractive properties, a particular interest has been shown in the B2-ordered intermetallic compound NiAl and its alloys.
The major objective of the project is to understand, model, design and develop the new class of NiAl-based in situ composites with tunable properties for high temperature services. A novel synergetic approach combining state-of-the-art computational thermodynamics with alloy design, processing and characterization, will be presented. On one hand, advanced computational thermodynamics will be used to create and optimize thermodynamics databases, which will be subsequently used for constitutional and phase equilibrium calculations. In parallel, diffusion and phase field models will be developed to model the eutectic microstructures resulting from the solidification processing. On the other hand, a combination of sophisticated alloy design and processing will be used to understand the solidification behavior and control the microstructure. Based on this knowledge the microstructure-property relationship will be established and alloys with superior properties will be tailored. The greatest challenge will be to obtain in a single alloy all the, frequently contradictory properties like high strength and good ductility, high fracture toughness and good formability, thermal stability and oxidation resistance.
Funding Organization: Spanish Ministry of Science and Innovation (Fundamental Research Programme)
Project Period: 2012 – 2015
Principal Investigator: Dr. Srdjan Milenkovic