Silver - Bismuth - Thallium
Introduction
The complete system was obtained by a computer optimization [76Zim1, 76Zim2], using thermodyamic and phase diagram data of the ternary system, DTA measurements of ternary liquidus temperatures and calorimetric measurements of heats of mixing of the ternary melt. The calculation was refined using new coefficients of the binary Bi-Tl system [78Kri].
Binary Systems
The liquidus of the system Ag-Tl [76Zim2] (Fig. 1) and some phase boundaries
of the system Tl-Bi [78Kri] (Fig. 2) are slightly different from those
assumed by [H]. For Ag-Bi the diagram of [H] is accepted.
Solid Phases
Except for the (Ag) solid solution in equilibrium with liquid, the extension into the ternary system is very small (see Table 1).Invariant Equilibria
Invariant equilibria are given in Table 2 and Fig. 3.Liquidus Surface
The liquidus surface is given in Fig. 4.Isothermal Sections
The isothermal section at 200C is given in Fig. 5.References
[76Zim1] B. ZIMMERMANN, "Rechnerische und Experimentelle Optimierung von Binären und Ternären Systemen aus Ag, Bi, Pb and Tl", Thesis, Universität Stuttgart, Germany (1976) (Equi. Diagram, Thermodyn., Experimental, #, 95)[76Zim2] B. ZIMMERMANN, E.-TH. HENIG and H.L. LUKAS, "Das System Ag-Bi-Tl, Berechnet aus den Optimierten Binären Randsystemen", Z. Metallkde., 67, 815-820 (1976) (Equi. Diagram, Thermodyn., Experimental, #, *, 13)
[78Kri] H. KRIEG, "Experimentelle und Rechnerische Bestimmung des Systems Bi-Pb-Tl", Diplomarbeit, Universität Stuttgart (1978) (Equi. Diagram, Experimental, 13)
Table 1: Solid Phases |
|||
| Phase /
Temperature Range (°C) |
Pearson
Symbol/ Prototype |
Lattice Parameters (pm) | Comments |
| (Ag) | cF4
Cu |
a = 408.62 | pure element 25C [P] |
| (Bi) | hR2
As |
a = 454.6
c = 1186.2 |
pure element 25C [P] |
| (Tl)(h) | cI2
W |
a = 388.2 | pure element 262C [P] |
| (Tl)(r) | hP2
Mg |
a = 345.66
c = 552.48 |
pure element 18C [P] |
| Tl3Bi | cF4
Cu |
a = 491.4 | at 79.9 at.% Tl [P] |
| Tl2Bi3 | hP3
B2Al |
a = 566.3
c = 337.8 |
[P] |
Table 2: Invariant Equilibria
| T (C)
Reaction |
Type | Phase | Composition (at.%)
Ag Bi Tl |
| 289.3
L+Tl3Bi (Ag)+(Tl)(h) |
U1 | L
(Ag) (Tl)(h) Tl3Bi |
2.3 5.8 91.9
95.5 0.0 4.5 0.0 6.0 94.0 0.0 7.5 92.5 |
| 197.3
L (Ag)+(Bi)+Tl2Bi3 |
E1 | L
(Ag) (Bi) Tl2Bi3 |
2.2 75.0 22.8
99.7 0.2 0.1 0.0 100.0 0.0 0.0 69.4 30.6 |
| 187.8
L (Ag)+Tl3Bi+Tl2Bi3 |
E2 | L
(Ag) Tl3Bi Tl2Bi3 |
1.1 46.8 52.1
99.6 0.1 0.3 0.0 40.5 59.5 0.0 55.1 44.9 |
| 144
(Tl)(h) Tl(r)+Tl3Bi(Ag) |
D1 | (Tl)(h)
(Tl)(r) Tl3Bi (Ag) |
0.0 2.3 97.9
0.0 1.3 98.7 0.0 5.3 94.7 100.0 0.0 0.0 |
