| Abstract Scope |
In the first part of this talk, we will report on the evolution, kinetics and mechanisms of γ', γ'', Ni2(Mo,W,Cr),η-Ni3Ti and δ precipitation and solute partitioning utilizing a combination of conventional TEM, HRTEM, STEM-HAADF, STEM-EDS and counterpart APT measurements and related analyses in Ni-Al-Cr-Nb (ATI 718 Plus, IN625) and Ni-Mo-W-Cr (Haynes 242, 244) alloys. In the second part of the talk, the temperature and strain rate dependence of strength, ductility and fracture behavior of the alloys, followed by results of the impact of advanced mechanical surface treatments like LSP and UNSM on near-surface microstructure, stress states, strengthening, fatigue and failure mechanisms at room and elevated temperatures, will be presented and discussed. |