Talks and Poster Presentations (without Proceedings-Entry):
E. Povoden-Karadeniz, M. Rath, A. Redermeier, E. Kozeschnik:
"Prediction of eta-phase Ni6AlNb evolution in Ni-base superalloys by computational thermokinetics";
Talk: Modelling and Simulation of Superalloys 2017,
Ruhr-Universität Bochum;
2017-03-29
- 2017-03-31.
English abstract:
In Ni-base superalloys, the η-phase (Ni3Ti) typically occurs in alloys with a high Ti/Al ratio after long-time exposure at high temperature. In the alloys IN-718 and ATI-718Plus, the phase Ni3Ti is not expected to occur due to the low Ti/Al ratio. However, in the alloy 718Plus a new plate-like η*-phase (Ni6AlNb) has been observed with the same hexagonal structure (D024) as the η-phase and a morphology and XRD pattern similar to the orthorhombic δ-phase (Ni3Nb).
The thermodynamic modeling of Ni3(Ti+Al+Nb) η*-phase is presented, and its role in 718Plus turbine disc alloy is discussed based on computational thermokinetic calculations. Based on thermokinetic time-temperature-precipitation simulation, competing precipitate evolution of η*-phase and δ-phase in alloy 718Plus is discussed.
Created from the Publication Database of the Vienna University of Technology.