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Effects of B and S on Ni3Al Grain Boundaries

  • A. F. Voter
  • S. P. Chen
  • R. C. Albert
  • A. M. Boring
  • P. J. Hay

Abstract

In many materials, the mechanical behavior is controlled by the grain boundary (GB) properties. An extreme example is the ordered alloy Ni3Al, which, as a single crystal, is ductile, while as a pure polycrystal, exhibits severe intergranular brittleness, making it useless as a technological material. However, it has been found [1] that doping Ni3Al that is slightly Ni-rich (76% Ni) with small amounts of boron (~l-2 atomic %) restores the ductility almost to the level of the single crystal. While it is known experimentally that B segregates to grain boundaries [1], the mechanism by which ductilization occurs is not known. We present here results of our initial investigation into the effects of impurities on Ni3Al grain boundaries, using interatomic potentials of the embedded atom [2,3] form, coupled with molecular statics techniques.

Keywords

Grain Boundary Interatomic Potential Embed Atom Method Symmetric Tilt Octahedral Interstitial Site 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • A. F. Voter
    • 1
  • S. P. Chen
    • 1
  • R. C. Albert
    • 1
  • A. M. Boring
    • 1
  • P. J. Hay
    • 1
  1. 1.Los Alamos National LaboratoryLos AlamosUSA

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