Phase equilibria in the Sm-Zr-Sb system at 1070 K

Article abstract of DOI:10.1016/S0925-8388(01)01882-5

Phase equilibria in the Sm-Zr-Sb system were investigated using x ray powder diffraction and metallographic analysis. The alloys were made in an electric arc furnace under an argon atmosphere using non-consumable tungsten electrode and a water-cooled tray. It was found that the system contained extended regions of solid solutions for SmSb. The results obtained were used in the construction of the isothermal cross-section of the Sm-Zr-Sb system at 1070 K.

Full text of DOI:10.1016/S0925-8388(01)01882-5

Journal of Alloys and Compounds 336 (2002) 187–189
L
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Phase equilibria in the Sm–Zr–Sb system at 1070 K
*
A .V . Morozkin
Department of Chemistry, Moscow Lomonosov State University, Leninskie Gory, V-234, GSP-3, 119899 Moscow, Russia
Received 3 August 2001; accepted 24 September 2001
Abstract
Phase equilibria in the Sm–Zr–Sb system were investigated by X-ray powder diffraction and the isothermal cross-section at 1070 K
was obtained. No ternary compounds were detected in this section.

2002 Elsevier Science B .V . All rights reserved.
Keywords: Rare earths, zirconium antimonides; Sm–Zr–Sb
1
. Introduction
by means of calculated patterns using the Rietan program
[5,6] in the isotropic approximation. A Neophot micro-
Interaction between the components in the Zr–Sb and
scope was employed for metallographic inspection (3250,
3500).
Sm–Sb binary system has been studied in Refs. [1–3]
Table 1). No compounds were detected in the Sm–Zr
system [4].
(
3
. Results and discussion
2
. Experimental detail
The results obtained were used in the construction of the
isothermal cross-section of the Sm–Zr–Sb system at 1070
K, presented in Fig. 2.
The present study was carried out on |20 alloys (Fig.
1
). The alloys were made in an electric arc furnace under
ZrSb , Zr Sb , Zr Sb, Zr Sb, Sm Sb, Sm Sb and
2
5
3
2
3
2
4
3
an argon atmosphere using non-consumable tungsten elec-
trode and a water-cooled copper tray. Antimony, samarium
and zirconium (purity of each component $99.99%) were
used as starting components. Titanium was used as a getter
during the melting process. The alloys were remelted three
times in order to achieve complete fusion and homoge-
neous composition. The melted alloys were subjected to an
anneal in evacuated quartz ampoules containing titanium
chips as a getter. The ampoules were placed in a resistance
furnace. The alloys were annealed at 1070 K for 2 weeks.
The samples were quenched from 1070 K in ice cold
water. The phase equilibria in the Sm–Zr–Sb system were
determined using X-ray phase analysis and metallographic
analysis. X-ray data were obtained on a diffractometer
DRON-3.0 (Cu Ka radiation, 2Q520–708, step 0.058, for
SmSb binary compounds were detected in this cross-
section (Table 1). The cell parameters of Sm Sb differ
2
from the data of Refs. [1,2]. We have not prepared the
SmSb2 compound. However, it may be present in the
isothermal section. We have not detected the Sm Sb
5
3
compound.
It was found that the system contains extended regions
of solid solutions for SmSb (|10% Zr) and Zr Sb (|5 at.%
2
Sm) (Table 1). The other binary compounds do not show
any visible solubility. The Zr Sb compound is very
5
3
unstable in air. A polycrystalline Zr Sb sample trans-
5
3
formed into amorphous powder after 2–3 days.
4. Conclusion
5
s per step). The diffractograms obtained were identified
We have detected no ternary compound in the iso-
thermal cross-section of the Sm–Zr–Sb system at 1070 K
although CeScSi-type RZrSb compounds were detected in
*
Fax: 17-095-932-8846.
E-mail address: morozkin@general.chem.msu.ru (A .V . Morozkin).
0
925-8388/02/$ – see front matter
 2002 Elsevier Science B .V . All rights reserved.
PII: S0925-8388(01)01882-5

1
88
A.V. Morozkin / Journal of Alloys and Compounds 336 (2002) 187–189
Table 1
Crystallographic data and temperature of the phase transition of compounds in the Sm–Zr–Sb system
b
Compounds
Space
group
Structure
type
a, nm
b, nm
c, nm
T , K
Refs.
a
1
2
3
.
.
.
Zr
Zr
P6 /mmc
Im3m
Mg
W
0.32321
0.3616
0.51477
1135
2125
[1]
[1]
3
a
Zr Sb
I4
I4
Ni P
1.135
1.1329(3)
0.565
0.5656(1)
[2]
This work
3
3
a
Zr Sb
Ni P
3
3
a
Zr Sb
tetr
P4
–
–
0.652
0.6497(5) . . .
0.6567(7)
0.790
0.7871(4) . . .
0.7942(7)
[2]
This work
2
Zr0.67 . . . 0.62Sm
0 . . . 0.05
a
0
Sb
.33
a
3
a
4
5
6
.
.
.
Zr Sb
P6 /mcm
Mn Si
0.8465
0.8488(5)
0.5806
0.5800(3)
[2]
This work
5
3
5
3
3
Zr Sb
P6 /mcm
Mn Si
5
3
3
5
a
2
a
ZrSb
ZrSb
Pnnm
Pnnm
ZrSb2
ZrSb2
1.49684
1.4932(8)
0.99672
0.9948(6)
0.38813
0.3875(1)
[2]
This work
2
Sb
Sb
R3m
As
Mg
0.43084
0.3369
1.1247
0.533
[1]
[1]
P6 /mmc
904
1580
3
a
2
7
8
.
.
SmSb
SmSb
Cmca
SmSb2
0.6171
0.6051
1.789
[1,3]
a
Fm3m
Fm3m
NaC1
NaC1
0.62706
0.6263(1) . . .
0.6170(1)
|2270
[1,3]
This work
Sm0.50 . . . 0.40Zr
0 . . . 0.10
a
0
Sb
.50
a
3
a
9
.
Sm Sb
I43d
I43d
Th P
3 4
0.9317
0.9298(1)
[1,3]
This work
4
Sm Sb
Th P
4
3
3
4
1
1
0.
1.
Sm Sb
P6 /mcm
Mn Si
0.910
0.640
[1,3]
5
3
a
3
5
3
Sm Sb
I4/mmm
I4/mmm
La Sb
0.4461
0.4484(1)
1.746
1.8040(8)
[1,2]
This work
2
2
a
Sm Sb
La Sb
2
2
a
1
2.
Sm
Sm
R3m
Im3m
a-Sm
W
0.3621
0.407
2.625
1190
1350
[1]
[1]
a
Compounds belong to the isothermal cross-section at 1070 K.
The temperatures listed refer to a phase transition (normal font) or to the melting temperature (bold font).
b
Fig. 1. Composition of samples investigated in the Sm–Zr–Sb system.
Fig. 2. Isothermal cross-section of the Sm–Zr–Sb system at 1070 K.

A.V. Morozkin / Journal of Alloys and Compounds 336 (2002) 187–189
189
Phases,Vol. 3, American Society for Metals, Metals Park, OH, 1985,
p. 3156.
3] G. Borzzone, A. Borsese, S. Delfino, R. Ferro, Z. Metalkd. 76 (3)
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Smj–Zr–Sb systems.
[
(
1985) 208–213.
[
4] E.I. Gladyshevskii, O.I. Bodak, in: Kristallohimia intermetalliches-
kih soedinenii redkozemel’nyh metallov,Vischa shkola, L’viv, 1982,
p. 48, (in Russian).
References
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[
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[
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1
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[