M.V. Bulanova et al. / Journal of Alloys and Compounds 345 (2002) 110–115
115
Table 3
systems, we consider the phases with a-GdSi and a-ThSi
structures to be individual compounds named CeSi22a1 and
CeSi22a2, rather than polymorphous modifications of the
2
2
Comparison of the predicted and experimental temperatures of invariant
reactions in Ce–Si system
Phase transformation
Temperature (8C)
same compound CeSi22a
.
Predicted
Experimental
Concluding, the present experimental results and the
predicted phase diagram (Fig. 1) correspond well. Table 3
shows the comparison of the temperatures of invariant
reactions as predicted and as determined experimentally.
L↔kg-Cel1Ce Si
625625
1460610
1590615
635
1500
1630
5
3
L1CeSi↔Ce Si
5
4
L↔CeSi
disilicide with a-ThSi structure in the alloy with 64.1 at%
2
References
Si. Therefore a continuous transition between the two
structures as reported in Ref. [11] is hardly possible. Then
thermal effects at |1575 8C can be attributed to the
invariant equilibrium L 1 CeSi22a1↔CeSi22a2. Hence,
congruent melting is valid for the CeSi22a1 phase with
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[13]. The distectic point occurs at a composition of about
[
6
3 at% Si.
(
The boundaries of the two-phase field CeSi22a1
1
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(
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[
[
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3
e–g) resulting from solid-state transformations allow us
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phase with a-GdSi structure.
2
(
Based on the absence of thermal effects in the range
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and also by analogy with the La–Si [13] and Pr–Si [12]
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