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Projects: Projects for Investigator
Reference Number EP/C536312/1
Title Accounting for Spatial and Temporal Variations of Microstructure on Creep-Related Behaviour of Nickel-Base Superalloys
Status Completed
Energy Categories Energy Efficiency(Transport) 25%;
Other Power and Storage Technologies(Electric power conversion) 25%;
Fossil Fuels: Oil Gas and Coal(Oil and Gas, Oil and gas combustion) 50%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields PHYSICAL SCIENCES AND MATHEMATICS (Metallurgy and Materials) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr D Dye
No email address given
Imperial College London
Award Type Standard
Funding Source EPSRC
Start Date 03 October 2005
End Date 02 January 2009
Duration 39 months
Total Grant Value £367,807
Industrial Sectors Aerospace; Manufacturing; Energy; Defence and Marine
Region London
Programme Materials, Mechanical and Medical Eng
Investigators Principal Investigator Dr D Dye , Materials, Imperial College London (99.997%)
  Other Investigator Dr M McLean , Materials, Imperial College London (0.001%)
Dr BA Shollock , Materials, Imperial College London (0.001%)
Professor PD (Peter ) Lee , Materials, University of Manchester (0.001%)
  Industrial Collaborator Project Contact , Siemens Power Generation, Inc (SPGI), USA (0.000%)
Project Contact , Rolls-Royce PLC (0.000%)
Web Site
Abstract Nickel-base superalloys are used in the hottest part of jet engines and power plant, in particular for the turbine blades that extract energy from the gas stream. These alloys are used at up to 80% of their melting point, a feat unreproduced in any other material system, and last for thousands of hours of service in a harsh, high load, oxidising environment. However, further improvements in fuelefficiency, resulting in cost improvements, reduced greenhouse-gas, NOW and SO2 emissions and reductions in weight, require that the operating temperature of these blades continues to increase. This requires that the creep of these alloys be predicted based on the microstructure of the alloys, in particular the evolution of the dislocation distribution, misfit between the Y-Ni3Al phase and theNimatrix, the size distribution of the 'y' and the composition of each phase, since in these alloys are composed of up to 14 different alloying elements.Historically, creep, ortime-dependent strain, in these materials has been predicted using empirical equations that are fitted to test data. At Imperial College, we have been developing a model that accounts explicitly for the microstructural features of these alloys, in particular the evolution of the dislocation distribution, since creep is the product of the generation, glide and entrapment of dislocations, which are line defects. However, we have not linked our models with models of microstructure before, insteadtreatingthe composition, distribution, misfit and volume fractions of the phases as fixed input data. In this proposal, we propose to link our model directly to enhanced versions of recently-developed precipitation models of these microstructural features, and then incorporate the entire model set into the finite element codes used by gas turbine manufacturers to design engines.Of course, data about the behaviour of these materials is tightly held by the engine manufacturers, because it is a keysource of their competitive advantage over each other and because the design assumptions they use inform the design and service of their products. For this program, we are partnering with the only two UK gas turbine manufacturers, Siemens-Westinghouse (Industrial gas turbines in Loncoln, UK) and Rolls-Royce (Aero engines in Derby, UK), who are each leaders in their sectors. They have agreed to provide us withdesign dataof the service conditions and both new and service-exposed blades in orderforus to validate our models against the actual behaviour observed in service. In addition, so as to examine clearly some of the more unusual features of the creep behaviour under tightly-controlled conditions, we will perform creep tests using both the virgin and service-exposed material. This combination of laboratory testing and actual component examination is extremely unusual in a scientific creep research program. Both the companies and the UK MOD as one of the biggest UK users of gasturbines are interested in using the models we produce to enhance their design and service-interval calculations, which will reduce their costs and enhance their competitive position. The research will also train botha PhD student and a postdoctoral researcher in creep and microstructure modelling and in advanced electron microscopy techniques, enabling them to move to the forefront of this critical field. Our past graduates of similar programs find wide employment with gas turbine manufacturers,research labs and universities both in the UK, EU and around the world. The research will be presented at leading international conferences, ensuring that it is used by the wider superalloys community
Publications (none)
Final Report (none)
Added to Database 01/01/07