γ(fcc)/γ(L12) 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, ΓW=1.2±0.2nm2, corresponding to a 5mJm2 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 5mJm2 due to W segregation. Similar calculations for {110} and {111} interfaces predict an increase of 1 and 9mJm2 in their energies, respectively, and therefore no heterophase segregation.

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.
S.
Hofmann
and
P.
Lejcek
,
J. Phys.
51
,
C1
179
(
1990
).
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
).
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
).
You do not currently have access to this content.