Numerical simulation of the simultaneous precipitation of δ and γ′ phases in the Ni-base superalloy ATI Allvac®718 Plus™

Rene Radis, Gerald A. Zickler, Martin Stockinger, Christof Sommitsch, Ernst Kozeschnik

Research output: Chapter in Book/Report/Conference proceedingConference contributionResearchpeer-review

Abstract

The present work deals with the numerical simulation of the precipitation kinetics of δ (Ni3(Nb, Al)) and γ′ (Ni 3(Al, Ti, Nb)) phases in the commercial nickel-base superalloy ATI Allvac®718Plus™. Important precipitate parameters such as volume fraction, mean radius and number density are numerically calculated as a function of the heat treatment parameters time and temperature and compared to experimentally determined data. To match the experimentally observed kinetics, the predicted interfacial energy of the precipitates, as calculated for a sharp, planar phase boundary, is adjusted to take into account the interfacial curvature and entropic effects of a diffuse interface. Using these modified interfacial energies, the calculated results show excellent agreement with the experimental measurements. Finally, a calculated time-temperature-precipitation (TTP) diagram for concurrent δ and γ′ precipitation is presented, which clearly demonstrates strong kinetic interactions during simultaneous precipitation of these phases. Thus, the present study emphasizes the importance of carefully controlling the heat treatment parameters time and temperature during the production process of ATI Allvac®718Plus™, in order to achieve the desired microstructure and hence mechanical properties.

Original languageEnglish
Title of host publication7th International Symposium on Superalloy 718 and Derivatives 2010
Pages569-578
Number of pages10
Publication statusPublished - 1 Dec 2010
Event7th International Symposium on Superalloy 718 and Derivatives 2010 - Pittsburgh, PA, United States
Duration: 10 Oct 201013 Oct 2010

Publication series

Name7th International Symposium on Superalloy 718 and Derivatives 2010
Volume2

Conference

Conference7th International Symposium on Superalloy 718 and Derivatives 2010
CountryUnited States
CityPittsburgh, PA
Period10/10/1013/10/10

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Keywords

  • ATI Allvac®718 plus™
  • Delta
  • Gamma prime
  • Nickel-base superalloys
  • Numerical simulations
  • Precipitation kinetics

ASJC Scopus subject areas

  • Metals and Alloys

Cite this

Radis, R., Zickler, G. A., Stockinger, M., Sommitsch, C., & Kozeschnik, E. (2010). Numerical simulation of the simultaneous precipitation of δ and γ′ phases in the Ni-base superalloy ATI Allvac®718 Plus™. In 7th International Symposium on Superalloy 718 and Derivatives 2010 (pp. 569-578). (7th International Symposium on Superalloy 718 and Derivatives 2010; Vol. 2).