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Thermodynamic study of the Nb-Ru-Al system
a Fiorani J. M., a David N., b,c Coelho G., b Nunes C., a Vilasi M.
a Institut Jean Lamour, Université Nancy 1, FRANCE
b Departamento de Engenharia de Materiais − EEL- Universidade de São Paulo – Lorena-SP, BRASIL
c Centro Universitário de Volta Redonda (UniFoa), Volta Redonda-RJ, BRASIL
Thermodynamic study of the Nb-Ru-Al system Introduction
Context of this study
Nb alloys are potential candidates for ultra-high temperature structural applications.
Alloying additions and protective coatings are necessary in order to increase their oxydation and corroson resistance
→ HTSMAs→ SME + MT(above 800°C)NbRu
Nb-Ru-Al-……
CALPHAD
1
Thermodynamic study of the Nb-Ru-Al system Introduction
Context of this study
Nb alloys are potential candidates for ultra-high temperature structural applications.
Alloying additions and protective coatings are necessary in order to increase their oxydation and corroson resistance
→ HTSMAs→ SME + MT(above 800°C)NbRu
Nb-Ru-Al-……
CALPHAD
Outline
Nb-Ru
Ru-Al
Nb-Al
Nb-Ru-Al
Conclusion
1
Thermodynamic study of the Nb-Ru-Al system
Nb-Ru system
Nb-Ru
Nb-Ru system
T. B. MASSALSKI, “Binary Alloy Phase Diagrams” second edition, ASM International (1990)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
2
T. B. MASSALSKI, “Binary Alloy Phase Diagrams” second edition, ASM International (1990)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
2
T. B. MASSALSKI, “Binary Alloy Phase Diagrams” second edition, ASM International (1990)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Ideal Stoechiometry → x(Ru) = 0.625
2
T. B. MASSALSKI, “Binary Alloy Phase Diagrams” second edition, ASM International (1990)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Ideal Stoechiometry → x(Ru) = 0.625
Observed at x(Ru) ∼ 0.66
Ru2Nb
2
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Phase diagram data from powder metallurgy synthesis and XRD + EPMA
3
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Phase diagram data from powder metallurgy synthesis and XRD + EPMA
52.5 58.4 65.3 67.5 77.3 86.0
B2B2+
Ru2NbRu2Nb
Ru2Nb+
A3A3
x(Ru) %
1200 °C500 h
1 2 3 4annealed
3
67.6 77.4 80.0
Ru2NbRu2Nb
+A3
A3
x(Ru) %
1350 °C360 h
1 2
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Phase diagram data from powder metallurgy synthesis and XRD + EPMA
52.5 58.4 65.3 67.5 77.3 86.0
B2B2+
Ru2NbRu2Nb
Ru2Nb+
A3A3
x(Ru) %
1200 °C500 h
1 2 3 4
67.6 77.4 80.0 x(Ru) %
annealed
3
T = 1350 °Ct = 48 h
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Diffusion couple → 20 µm of Ru deposited by PVD on a Nb substrate
annealed
4
80
100
120
Mol
ar F
ract
ion
Nb
A3Ru2Nb
B2
T = 1350 °Ct = 48 h
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Diffusion couple → 20 µm of Ru deposited by PVD on a Nb substrate
annealed
0
20
40
60
0 10 20 30 40 50 60
Mol
ar F
ract
ion
Ru
Distance (micrometer)
4
80
100
120
Mol
ar F
ract
ion
Nb
A3Ru2Nb
B2 A2
T = 1350 °Ct = 48 h
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Diffusion couple → 20 µm of Ru deposited by PVD on a Nb substrate
annealed
0
20
40
60
0 10 20 30 40 50 60
Mol
ar F
ract
ion
Ru
Distance (micrometer)
← x(Ru) ∼ 20%
4
L
A2
A1B2
NbRu
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
NbRu2
5
L
A2
A1B2
NbRu
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
NbRu2
[Mas90] → T. B. MASSALSKI, “Binary Alloy Phase Diagrams”, second edition, ASM International (1990)5
Enthalpies of formation (not considered in the present optimization)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
[Cur2005] → S. Curtarolo, D. Morgan, G. Ceder, CALPHAD, 29, (2005)
[Gho2007] → G. Ghosh, G.B. Olson, Acta Mater. 55 (2007)
6
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Enthalpies of formation (not considered in the present optimization)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
[Cur2005] → S. Curtarolo, D. Morgan, G. Ceder, CALPHAD, 29, (2005)
[Gho2007] → G. Ghosh, G.B. Olson, Acta Mater. 55 (2007)
[Ben2009] → My.Y. Benarchid, N. David, J-M. Fiorani, M. Vilasi, T. Benlaharche, Thermochimica Acta 482 (2009)6
Enthalpies of formation (not considered in the present optimization)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
[Cur2005] → S. Curtarolo, D. Morgan, G. Ceder, CALPHAD, 29, (2005)
[Gho2007] → G. Ghosh, G.B. Olson, Acta Mater. 55 (2007)
[Ben2009] → My.Y. Benarchid, N. David, J-M. Fiorani, M. Vilasi, T. Benlaharche, Thermochimica Acta 482 (2009)6
Enthalpies of formation (not considered in the present optimisation)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
[Cur2005] → S. Curtarolo, D. Morgan, G. Ceder, CALPHAD, 29, (2005)
[Gho2007] → G. Ghosh, G.B. Olson, Acta Mater. 55 (2007)
[Ben2009] → My.Y. Benarchid, N. David, J-M. Fiorani, M. Vilasi, T. Benlaharche, Thermochimica Acta 482 (2009)6
Liquid
(Nb,Ru)
A3
(Nb,Ru)
A2(Nb,Ru)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Thermodynamic models
ϕϕϕϕ GGGG ex
id
re
f++=
( )..
.
)x(xL)x(xLLxx
) )(xx)(x(xRT
GxGxG
BAA,
B
BAA,
B
A,
B
BA
BBAA
BBAA
+−+−++
++
+=
2210
ln
ln ϕϕϕ
ϕϕϕ
TbaL i,
j
νi
,j
νi
,j
ν ϕϕϕ +=Binary Parameters
7
Li
qN
b,
Ru
L0 - 133800
Li
qN
b,
Ru
L1 - 12970
Liquid
(Nb,Ru)
30 AN
b,
Ru
L - 80655 – 20.181 T
31 AN
b,
Ru
L - 25779
A3
(Nb,Ru)
20 AN
b,
Ru
L - 85598 – 19.681 TA2
(Nb,Ru)
2
3
2
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
Thermodynamic models
ϕϕϕϕ GGGG ex
id
re
f++=
( )..
.
)x(xL)x(xLLxx
) )(xx)(x(xRT
GxGxG
BAA,
B
BAA,
B
A,
B
BA
BBAA
BBAA
+−+−++
++
+=
2210
ln
ln ϕϕϕ
ϕϕϕ
TbaL i,
j
νi
,j
νi
,j
ν ϕϕϕ +=Binary Parameters
7
B2
(Nb,Ru) (Nb,Ru)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
(A,B) (A,B)
'Ay '
By ''Ay
(A, B)
''By A
''A
'A xyy ==
B'
'B'B xyy ==
''A
'A yy ≠
''B
'B yy ≠
B2 A2
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
''B
'B yy ≠
8
22/B
AGGor
d∆
Gdi
sGib
bs E
nerg
y
Mole fractionA B
(A,B) (A,B)
'Ay '
By ''Ay
(A, B)
''By A
''A
'A xyy ==
B'
'B'B xyy ==
''A
'A yy ≠
''B
'B yy ≠
B2 A2
Thermodynamic study of the Nb-Ru-Al system Nb-RuS
ite fr
actio
n
Mole fractionA B
'Ay
'By
''Ay
''By
''B
'B yy ≠
)x
)
(yG(y
)
G((x)
GG BBA/B
A =−+= 22222
Gor
d∆Gd
is
ΔG
GG or
d
di
s
/B
A +=22
Compound Energy Formalism
orddis dis8
( ) ( )[ ]
..
..
.
L)y(yyyyL)y(yyyyLy)y(yyyLy)y(yyy
LyyyLyyyLyyyLyyy
GyyGyyGyyGyy
)(yy)(yyb)(yy)(yyaRT
G
A:
A,
B
''B
''A
''B
''A
'AB
:A
,B
''B
''A
''B
''A
'B
A,
B:
A
''A
'B
'A
'B
'AA
,B
:B
''B
'B
'A
'B
'A
A:
A,
B
''B
''A
'AB
:A
,B
''B
''A
'B
A,
B:
A
''A
'B
'AA
,B
:B
''B
'B
'A
B:
A
''A
'BA
:B
''B
'AB
:B
''B
'BA
:A
''A
'A
''B
''B
''A
''A
'B
'B
'A
'A
+−+−+
−+−+
++
++
++++
+++=
ϕϕ
ϕϕ
ϕϕ
ϕϕ
ϕϕϕϕ
ϕ
11
11
00
00
ln
ln
ln
ln
ϕGid←←←←
ϕGre
f←←←←
ϕGex←←←←
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
..
..
.
+
9
( ) ( )[ ]
..
..
.
L)y(yyyyL)y(yyyyLy)y(yyyLy)y(yyy
LyyyLyyyLyyyLyyy
GyyGyyGyyGyy
)(yy)(yyb)(yy)(yyaRT
G
A:
A,
B
''B
''A
''B
''A
'AB
:A
,B
''B
''A
''B
''A
'B
A,
B:
A
''A
'B
'A
'B
'AA
,B
:B
''B
'B
'A
'B
'A
A:
A,
B
''B
''A
'AB
:A
,B
''B
''A
'B
A,
B:
A
''A
'B
'AA
,B
:B
''B
'B
'A
B:
A
''A
'BA
:B
''B
'AB
:B
''B
'BA
:A
''A
'A
''B
''B
''A
''A
'B
'B
'A
'A
+−+−+
−+−+
++
++
++++
+++=
ϕϕ
ϕϕ
ϕϕ
ϕϕ
ϕϕϕϕ
ϕ
11
11
00
00
ln
ln
ln
ln
ϕGid←←←←
ϕGre
f←←←←
ϕGex←←←←
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
..
..
.
+
22 BB
:A
BA
:B
GG =
2020 BA
:A
,B
BA
,B
:A
LL =2020 B
B:
A,
B
BA
,B
:B
LL =2121 B
A:
A,
B
BA
,B
:A
LL =
2121 BB
:A
,B
BA
,B
:B
LL =
Constraints
9
B2
(Nb,Ru) (Nb,Ru)
22 BR
u:
Nb
BN
b:
Ru
GG = - 14037 + 0.88 T
2121 BR
u:
Nb
,R
u
BN
b,
Ru
:R
u
LL = - 11291
2020 BN
b:
Nb
,R
u
BN
b,
Ru
:N
b
LL = 14037 - 0.88 T
2020 BR
u:
Nb
,R
u
BN
b,
Ru
:R
u
LL = 14037 - 0.88 T3
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
10
NbRu2
(Nb,Ru)0.375 (Ru)0.625
(A,B) (A,B)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
(A,B)0.375 (A,B)0.625
11
NbRu2
(Nb,Ru)0.375 (Ru)0.625
(A,B) (A,B)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
(A,B)0.375 (A,B)0.625
'Ay '
By
0=''Ay
1=''By
( )[ ]
ϕ
ϕϕ
ϕ
A,
B:
B
'B
'A
A:
B
'AB
:B
'B
'B
'B
'A
'A
LyyGyGy
)(yy)(yyaRT
G
0
ln
ln
+
++
+=
11
NbRu2
(Nb,Ru)0.375 (Ru)0.625
2Nb
Ru
Nb
:R
u
G - 17140 – 7.4 T
20 Nb
Ru
Nb
,R
u:
Ru
L - 51044 + 1.08 T
2Nb
Ru
Ru
:R
u
G 40000
(A,B) (A,B)
5
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
(A,B)0.375 (A,B)0.625
'Ay '
By
0=''Ay
1=''By
( )[ ]
ϕ
ϕϕ
ϕ
A,
B:
B
'B
'A
A:
B
'AB
:B
'B
'B
'B
'A
'A
LyyGyGy
)(yy)(yyaRT
G
0
ln
ln
+
++
+=
11
Li
qN
b,
Ru
L0 - 133800
Li
qN
b,
Ru
L1 - 12970
Liquid
(Nb,Ru)
30 AN
b,
Ru
L - 80655 – 20.181 T
31 AN
b,
Ru
L - 25779
A3
(Nb,Ru)
20 AN
b,
Ru
L - 85598 – 19.681 TA2
(Nb,Ru)
2
3
2
Thermodynamic study of the Nb-Ru-Al system Nb-Ru
NbRu2
(Nb,Ru)0.375 (Ru)0.625
2Nb
Ru
Nb
:R
u
G - 17140 – 7.4 T
20 Nb
Ru
Nb
,R
u:
Ru
L - 51044 + 1.08 T
2Nb
Ru
Ru
:R
u
G 40000
B2
(Nb,Ru) (Nb,Ru)
22 BR
u:
Nb
BN
b:
Ru
GG = - 14037 + 0.88 T
2121 BR
u:
Nb
,R
u
BN
b,
Ru
:R
u
LL = - 11291
2020 BN
b:
Nb
,R
u
BN
b,
Ru
:N
b
LL = 14037 - 0.88 T
2020 BR
u:
Nb
,R
u
BN
b,
Ru
:R
u
LL = 14037 - 0.88 T3
5
15
12
Thermodynamic study of the Nb-Ru-Al system
Ru-Al system
Ru-Al
Ru-Al system
[Pri2003 ] → S.N. Prins, L.A. Cornish, W.E. Stumpf,B. Sundman, Calphad 2003, 27(1) (2003)
Thermodynamic study of the Nb-Ru-Al system Ru-Al
13
[Pri2003 ] → S.N. Prins, L.A. Cornish, W.E. Stumpf,B. Sundman, Calphad 2003, 27(1) (2003)
Thermodynamic study of the Nb-Ru-Al system Ru-Al
[Müc2005 ] → F. Mücklich, N. Ilic, Intermetallics 13 (2005)
13
Tem
pera
ture
(K
)
[This work][Müc2005 ] → F. Mücklich, N. Ilic, Intermetallics 13 (2005)
Thermodynamic study of the Nb-Ru-Al system Ru-Al
Mole fraction Ru
Tem
pera
ture
(K
)
14
Thermodynamic study of the Nb-Ru-Al system Ru-Al
[Müc2005 ] → F. Mücklich, N. Ilic, Intermetallics 13 (2005)15
Enthalpies of formation → B2
Thermodynamic study of the Nb-Ru-Al system Ru-Al
[Jun92] → W. G. Jung, O. J. Kleppa, Met. Trans. B, 23B, (1992)
[Su2005] → H. N. Su, P. Nash, J. of Alloys and Compounds, 403, (2005)
[Lin92] → W. Lin, J. Xu, A. J. Frreeman, J. Mat. Res., 7, (1992)
[Ngu99] → D. Nguyen-Manh, D. G. Petitfor, Intermetallics, 7, (1999)
[Gar2003] → P. Gargano, H. Mosca, G. Bozzolo, R. D. Noebe, Scripta Materialia, 48, (2003)16
Li
qR
u,
Al
L0 - 106693 – 2.762 T
Li
qR
u,
Al
L1 - 16488 – 19.662 T
Liquid
(Ru,Al)
30 AR
u,
Al
L - 163141 + 28 T
31 AR
u,
Al
L - 46065
A3
(Ru,Al)
10 AR
u,
Al
L - 10000A1
(Ru,Al)
4
3
1
Thermodynamic study of the Nb-Ru-Al system Ru-Al
20 AR
u,
Al
L - 169171 + 34 TA2
(Ru,Al)
B2
(Ru,Al) (Ru,Al)
22 BR
u:
Al
BA
l:
Ru
GG = - 37529
2121 BR
u:
Al
,R
u
BA
l,
Ru
:R
u
LL = - 1514
2020 BR
u:
Al
,R
u
BA
l,
Ru
:R
u
LL = 37529 - 1514
2020 BA
l:
Al
,R
u
BA
l,
Ru
:A
l
LL = 37529 - 27136
2121 BA
l:
Al
,R
u
BA
l,
Ru
:A
l
LL = 27136
2
3
13
17
6Ru
Al
Al
:R
u
G - 33082 + 4.492 TRuAl6
(Al)0.833(Ru)0.167
13
4Al
RuAl
:R
u
G - 43032 + 3.086 TRu4Al13
(Al)0.765(Ru)0.235
52Al
RuAl
:R
u
G - 40790 – 0.982 TRu2Al5
(Al)0.714(Ru)0.286
RuAl2
10
Thermodynamic study of the Nb-Ru-Al system Ru-Al
2Ru
Al
Al
:R
u
G - 46534 + 0.058 TRuAl2
(Al)0.667(Ru)0.333
32Al
RuAl
:R
u
G - 49810 + 0.981 TRu2Al3
(Al)0.6(Ru)0.4
bBaAA
:B
SE
RB
SE
RA
bBaA GGba
aGba
aG +
+
+
+
=
18
Thermodynamic study of the Nb-Ru-Al system
Nb-Al system
Nb-Al
Nb-Al system
T. B. MASSALSKI, “Binary Alloy Phase Diagrams” second edition, ASM International (1990)
Thermodynamic study of the Nb-Ru-Al system Nb-Al
19
Liq (Al,Nb)
A1 (Al,Nb)
A2 (Al,Nb)
AlNb3 (Al,Nb)0.75(Nb)0.25
[Sau98 ] → N. Saunders in COST 507-(1998)
Tem
pera
ture
(K
)Thermodynamic study of the Nb-Ru-Al system Nb-Al
(Al)8(Nb)4(Al,Nb)18σ
Al3Nb (Al)0.75(Nb)0.25
Mole fraction Al
Tem
pera
ture
(K
)
20
Thermodynamic study of the Nb-Ru-Al system
Nb-Ru-Al system
Nb-Ru-Al
Nb-Ru-Al system
[Cer93 ] → P. Cerba, M. Vilasi, B. Malaman, J. SteinmetzJ. of Alloys and Compounds, 201(1-2), (1993)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
T = 1100 °C
21
[Cer93 ] → P. Cerba, M. Vilasi, B. Malaman, J. SteinmetzJ. of Alloys and Compounds, 201(1-2), (1993)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
T = 1100 °C
[Hoh2002] → J. Hohls, P.J. Hill, I.M. WolffMat. Sci. and Eng. A329–331, (2002)T = 1200 °C
21
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Phase diagram data from powder metallurgy synthesis T = 1100 °C t = 1000 h
[Cer93 ] → P. Cerba, M. Vilasi, B. Malaman, J. SteinmetzJ. of Alloys and Compounds, 201(1-2), (1993)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
T = 1100 °C
T = 1200 °C
A3
B2 B2
L21
T = 1100 °C
21
[Hoh2002] → J. Hohls, P.J. Hill, I.M. WolffMat. Sci. and Eng. A329–331, (2002)
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Isothermal sectionT = 1100 °C
22
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Isothermal sectionT = 1100 °C
Redlich-Kister Muggianu
Liquid (Nb,Ru,Al)
B2 (Nb,Ru,Al) (Nb,Ru,Al)
A1 (Nb,Ru,Al)
A2 (Nb,Ru,Al)
A3 (Nb,Ru,Al)
22
∑=
−=0ν
νBAA
,B
νBA
ex )x(xLxxG ϕ
∑=
−+0ν
νCAA
,C
νCA )x(xLxx ϕ
∑=
−+0ν
νCBB
,C
νCB )x(xLxx ϕ
Binary Parameters
RuAl6 (Al)0.833(Ru)0.167
Ru4Al13 (Al)0.765(Ru)0.235
Ru2Al5 (Al)0.714(Ru)0.286
NbRu2 (Nb,Ru)0.375 (Ru)0.625 Nb-Ru
Ru-Al
Phases without a considered ternary extension
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Isothermal sectionT = 1100 °C
RuAl2 (Al)0.667(Ru)0.333
Ru2Al3 (Al)0.6(Ru)0.4
(Al)8(Nb)4(Al,Nb)18σ
Al3Nb (Al)0.75(Nb)0.25
AlNb3 (Al,Nb)0.75(Nb)0.25
Nb-Al
23
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Isothermal sectionT = 1100 °C
L21 (Nb,Al) (Ru)
12LA
l:
Ru
G - 51542
12LN
b:
Ru
G - 34513
120 LA
l,
Nb
:R
u
L - 44910
C14 (Nb)0.333 (Ru,Al)0.667
14
CN
b:
Ru
G - 16852
14
CN
b:
Al
G - 109300
14
0 CN
b:
Ru
,A
l
L - 343000
6
24
Ru
Isothermal section T = 1100 °C
Calculated Experimental
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
25
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Enthalpies of formation (not considered in the present optimisation)
[Gho2007] → G. Ghosh, G.B. Olson, Acta Mater. 55 (2007)
[Wat98] → R.E. Watson, M. Weinert, M. Alatalo, Phys. Rev. B 57 (1998)
[Ben2009] → My.Y. Benarchid, N. David, J-M. Fiorani, M. Vilasi, T. Benlaharche, Thermochimica Acta 482 (2009)
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A3
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Liquidus projection (without L21 and C14)
B2
A2
AlNb3
σ
Al3Nb
RuAl2
Ru2Al5
Ru4Al13
RuAl2
A1
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A3
→Max
L + AlNb3 ↔ σ + A2 1881 °C
L + σ ↔ Al3Nb + B2 1374 °C
L + Ru4Al13 ↔ Al3Nb + Ru2Al5 1345 °C
L + Ru4Al13 ↔ Al3Nb + RuAl6 734 °C
L + Al3Nb ↔ RuAl6 + A1 660 °C
L ↔ Al3Nb + Ru2Al5 + RuAl2 1345 °C
L ↔ Al3Nb + RuAl2 + B2 1315 °C
Peritectic
Eutectic
Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Liquidus projection (without L21 and C14)
B2
A2
AlNb3
σ
Al3Nb
RuAl2
Ru2Al5
Ru4Al13
RuAl2
A1
→Max
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Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
Arc-melted alloys + XRD + SEM
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Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
L2
L21 → melts congruently
Arc-melted alloys + XRD + SEM
L21
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Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
L2 Ternary eutectic
L21 → melts congruently
C14 → melts congruently
Arc-melted alloys + XRD + SEM
σσσσ
C14
NbAl3
RuAl2
L21
B2
Ternary eutectic
Maximum
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Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
L ↔ C14 + NbAl3 + RuAl2
17 Nb17 Ru66 Al
L↓
C14 (light gray)
NbAl3(dark gray)
RuAl2(gray)
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Thermodynamic study of the Nb-Ru-Al system Nb-Ru-Al
L ↔ C14 + NbAl3 + RuAl2
17 Nb17 Ru66 Al
L ↔ C14 + NbAl3 + σ
40 Nb5 Ru55 Al
L↓
L↓
C14 (light gray)
NbAl3(dark gray)
RuAl2(gray)
C14(gray)
σ(light gray)
NbAl3(dark gray)
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Thermodynamic study of the Nb-Ru-Al system Conclusion
New assessment(Nb-Ru)
→ Enthalpies (B2 and A3)
→ Displacive transformations
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Thermodynamic study of the Nb-Ru-Al system Conclusion
Thermodynamic study of the Nb-Ru-Al system Conclusion
New assessment(Nb-Ru)
→ Enthalpies (B2 and A3)
→ Displacive transformations
New assessmentNew assessment(Ru-Al-Nb)
→ New experiments (DTA) → Temperatures of invariant reactions, liquidus …
→ Enthalpies (L21 and C14)
→ Diagram data (T = 1100 °C, Liquidus projection)
→ New Nb-Ru assessment
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