Development of NB-based Alloys for Turbine Applications

Current Ni-based alloys used in turbine blade applications are operating at 1100°C which is approximately 90% of the solidus of Ni-based alloys. Further increases in temperature can be achieved only through the use of alloys with higher solidus temperatures such as refractory alloys which include Mo, Nb, W, Ta alloys. The objective of the project is to use computational modeling tools and advanced characterization to develop two classes of Nb alloys with the required density, creep rupture life and oxidation resistance at 1300°C and compatible with silicide coatings that are currently commercially available or other coatings that will be developed as part of the ULTIMATE program. University of Kentucky will use advanced electron microscopy techniques to characterize the structure and chemistry of the matrix and second phase precipitates in selected Nb alloys to assist in alloy design and to correlate mechanical properties with microstructure.