heterophase interfaces in a Ni-based superalloy are investigated using atom-probe tomography and first-principles calculations. Flat {100} interfaces exhibit a confined (nonmonotonic) Gibbsian interfacial excess of tungsten, , corresponding to a decrease in interfacial free energy. Conversely, no measurable segregation of W is detected at curved interfaces. First-principles calculations for a Ni–Al–W system having a {100} interface indicate a decrease in the interfacial energy of due to W segregation. Similar calculations for {110} and {111} interfaces predict an increase of 1 and in their energies, respectively, and therefore no heterophase segregation.
REFERENCES
1.
R. C.
Reed
, The Superalloys: Fundamentals and Applications
(Cambridge University Press
, New York
, 2006
), p. 372
.2.
K. E.
Yoon
, D.
Isheim
, R. D.
Noebe
, and D. N.
Seidman
, Interface Sci.
9
, 249
(2001
).3.
K. E.
Yoon
, R. D.
Noebe
, and D. N.
Seidman
, Acta Mater.
55
, 1145
(2007
).4.
C. K.
Sudbrack
, D.
Isheim
, R. D.
Noebe
, N. S.
Jacobson
, and D. N.
Seidman
, Microsc. Microanal.
10
, 355
(2004
).5.
D. N.
Seidman
, Annu. Rev. Mater. Res.
37
, 127
(2007
).6.
T. F.
Kelly
and M. K.
Miller
, Rev. Sci. Instrum.
78
, 031101
(2007
).7.
B. W.
Krakauer
and D. N.
Seidman
, Rev. Sci. Instrum.
63
, 4071
(1992
).8.
Y.
Zhou
, C.
Booth-Morrison
, and D. N.
Seidman
, Microsc. Microanal.
14
, 571
(2008
).9.
O. C.
Hellman
, J. A.
Vandenbroucke
, J.
Rüsing
, D.
Isheim
, and D. N.
Seidman
, Microsc. Microanal.
6
, 437
(2000
).10.
B. W.
Krakauer
and D. N.
Seidman
, Phys. Rev. B
48
, 6724
(1993
).11.
O. C.
Hellman
and D. N.
Seidman
, Mater. Sci. Eng., A
327
, 24
(2002
).12.
R.
Herschitz
and D. N.
Seidman
, Acta Metall.
33
, 1547
(1985
).13.
M. S. A.
Karunaratne
, P.
Carter
, and R. C.
Reed
, Mater. Sci. Eng., A
281
, 229
(2000
).14.
15.
A.
Seki
, D. N.
Seidman
, Y.
Oh
, and S. M.
Foiles
, Acta Metall. Mater.
39
, 3167
(1991
).16.
G.
Kresse
and J.
Furthmuller
, Comput. Mater. Sci.
6
, 15
(1996
).17.
G.
Kresse
and J.
Hafner
, Phys. Rev. B
49
, 14251
(1994
).18.
G.
Kresse
and D.
Joubert
, Phys. Rev. B
59
, 1758
(1999
).19.
D.
Blavette
, E.
Cadel
, C.
Pareige
, B.
Deconihout
, and P.
Caron
, Microsc. Microanal.
13
, 464
(2007
).20.
Y.
Mishin
, Acta Mater.
52
, 1451
(2004
).21.
C.
Booth-Morrison
, Z.
Mao
, R. D.
Noebe
, and D. N.
Seidman
, Appl. Phys. Lett.
93
, 033103
(2008
).22.
E. A.
Marquis
, D. N.
Seidman
, M.
Asta
, and C.
Woodward
, Acta Mater.
54
, 119
(2006
).23.
C. K.
Sudbrack
, T. D.
Ziebell
, R. D.
Noebe
, and D. N.
Seidman
, Acta Mater.
56
, 448
(2008
).© 2008 American Institute of Physics.
2008
American Institute of Physics
You do not currently have access to this content.