• PDF / 204,025 Bytes
• 2 Pages / 593.972 x 792 pts Page_size
• 42 Downloads / 237 Views

DOWNLOAD

REPORT

---

upplemental Literature Review: Section III

Si-V (Silicon-Vanadium) H. Okamoto

The Si-V phase diagram in [Massalsi2] was redrawn from [1985Smi]. [2007Zha] noticed that the eutectoid decomposition temperature of V6Si5 shown at 1160 °C in [1985Smi], which was quoted from [1985Sto], was actually 1160 K (887 °C). A further investigation by [2007Zha] using x-ray powder diffraction indicated that the decomposition temperature of V6Si5 is below 500 °C. Figure 1 shows the Si-V phase diagram calculated by [2008Zha]. The experimental data points used in the modeling were nearly the same as those used by [1985Smi], but a few additional experiments were carried out to clarify ambiguous areas. Table 1

Table 1 shows Si-V crystal structure data given by [1985Smi]. The composition range of phases was modified in accordance with Fig. 1.

References 1985Smi: J.F. Smith, The Si-V (Silicon-Vanadium) System: Addendum, Bull. Alloy Phase Diagr., 1985, 6(3), p 266-271 1985Sto: E.K. Storms and C.E. Myers, Thermodynamics and Phase Equilibria in the Vanadium-Silicon System, High Temp. Sci., 1985, 20, p 87-96

Si-V

Phase

Composition, at.% V

Pearson symbol

Space group

Strukturbericht designation

Prototype

(Si) Si2V Si5V6 Si3V5 SiV3 (V)

0 33.3 55 62.5 74.5-80.1 95.2-100

cF8 hP9 oI44 tI32 cP8 cI2

Fd 3m P6222 Immm I4/mcm Pm3n Im3m

A4 C40 ... D8m A15 A2

C (diamond) CrSi2 Nb6Sn5 W5Si3 Cr3Si W

Weight Percent Vanadium 0

10

20

30

50

40

60

90

100

1987°C

2000

1914°C

L 1683°C

1600

1910°C

89.1

80.1

1837°C

95.2

(V)

1667°C 42.4

1414°C 1400

SiV3

1921°C

1800

1631°C

1395°C 5.3

Si5V6

1000

(Si) 800

Si3V5

1200

Si2V

Temperature,°C

80

70

600 459°C

400 0 Si

10

20

30

40

50

60

70

80

Atomic Percent Vanadium

90

100 V

Fig. 1 Si-V phase diagram

Journal of Phase Equilibria and Diffusion Vol. 31 No. 4 2010

409

Section III: Supplemental Literature Review 2007Zha: C. Zhang, J. Wang, Y. Du, and W. Zhang, An Investigation on the Thermodynamic Stability of V6Si5, J. Mater. Sci., 2007, 42, p 7046-7048

410

2008Zha: C. Zhang, Y. Du, W. Xiong, H. Xu, P. Nash, Y. Ouyang, and R. Hu, Thermodynamic Modeling of the V-Si System Supported by Key Experiments, Calphad, 2008, 32, p 320-325

Journal of Phase Equilibria and Diffusion Vol. 31 No. 4 2010