Time: 4:00 p.m.
Place: IC 04/408
Panos Tsakiropoulos, Department of Materials Science and Engineering, The University of Sheffield, Sheffield, United Kingdom
Alloys with capabilities beyond those of Ni-based superalloys would enable future aero-engines to meet environmental and performance targets. The message for materials development is “alloys, processes and design must work hand in hand to lead to successful new technologies”. The presentation will discuss this message (i) to highlight the major challenges that the materials community is faced with, (ii) to draw attention to breakthroughs and (iii) to discuss future research priorities.
The presentation will be based on Nb-silicide in situ composites (or Nb-silicide based alloys) in which the important phases are the bcc solid solution, Nbss, and the tetragonal Nb5Si3 and Nb3Si silicides. Achieving a balance of mechanical and environmental properties is a major challenge to the alloy designer given the diverse properties of the phases and processing difficulties. As part of the discussion of (i) to (iii), the presentation will briefly review the key properties of the above phases and will concentrate on explaining how they influence room and elevated temperature mechanical properties and oxidation resistance. Breakthroughs in improving the properties of these phases will be highlighted and approaches to alloy design to optimize mechanical and environmental properties will be discussed.