Skip to main content
Log in

Quantitative differential thermal analysis of polymorphic transformations in LaGe1.8 and SmSi2

  • Published:
Powder Metallurgy and Metal Ceramics Aims and scope

Abstract

The possibility of using quantitative differential thermal analysis to investigate phase transformations is examined. The temperature, enthalpy, and entropy of polymorphic transformations in LaGe1.8 and SmSi2 are determined: Ttr = 724 K, ΔtrH = 1635 ± 79 J · mole−1, ΔtrS = 2.3 ± 0.1 J · mole−1 · K−1 (LaGe1.8); Ttr = 658 K, ΔtrH = 1384 ± 69 J · mole−1, ΔtrS = 2.1 ± 0.1 J · mole−1 · K−1 (SmSi2).

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Yu. I. Buyanov, T. Ya. Velikanova, S. P. Luzan, et al., “Relationships governing the construction of equilibrium diagrams of REM-(Si, Ge) binary systems and thermodynamics of alloy formation,” Powder Metall. Met. Ceram., 35, No. 7–8, 410–422 (1996).

    Article  Google Scholar 

  2. E. I. Gladyshevskii, Crystal Chemistry of Silicides and Germanides [in Russian], Metallurgiya, Moscow (1971), p. 216.

    Google Scholar 

  3. Yu. I. Buyanov, “On defects of crystal lattices of rare earth disilicides,” in: Silicides and Their Application in Technology, Inst. Probl. Materialoved. AN USSR, Kiev (1990), pp. 12–17.

    Google Scholar 

  4. “Phase equilibria in binary and multicomponent systems, thermodynamics of alloys and metal chemistry of intermetallides and transient metal compounds. Scientific basis for developing special-purpose multicomponent alloys,” Report on Subject 1.6.2.36, Inst. Probl. Materialoved. National Academy of Sciences of Ukraine, Kiev (1994), p. 133.

  5. A. S. Bolgar, N. P. Gorbachuk, and L. V. Blinder, “Enthalpies of Gd5Si3, Gd5Si4, GdSi, and GdSi1.88 silicides in a temperature range of 298.15–2200 K. Enthalpy of mixing,” Teplofiz. Vys. Temp., 34, No. 4, 541–545 (1996).

    Google Scholar 

  6. L. V. Gurvich, I. V. Veich, and V. A. Medvedev, Thermodynamic Properties of Individual Substances: Handbook [in Russian], 3rd ed., Nauka, Moscow (1981), Vol. III, Book 1, p. 472; Moscow (1982), Vol. IV, Book 1, p. 623.

    Google Scholar 

  7. L. G. Berg, Introduction to Thermography [in Russian], Nauka, Moscow (1969), p. 395.

    Google Scholar 

  8. R. Hultgren, R. D. Desai, D. T. Hawkins, and et al., Selected Values of the Thermodynamic Properties of the Elements, ASM, Metals Park, Ohio (1973), p. 636.

    Google Scholar 

  9. M. M. Antonova, Properties of Hydrides [in Russian], Naukova Dumka, Kiev (1965), p. 60.

    Google Scholar 

  10. B. A. Kolachev, R. E. Shalin, and A. A. Il’in, Alloys as Hydrogen Accumulators: Handbook [in Russian], Metallurgiya, Moscow (1995), p. 384.

    Google Scholar 

  11. A. S. Bolgar, A. V. Blinder, and N. P. Gorbachuk, “Heat capacity of lanthanum germanides at 60–300 K,” Zh. Fiz. Khim., 71, No. 4, 583–586 (1997).

    Google Scholar 

  12. N. P. Gorbachuk, A. S. Bolgar, A. V. Blinder, and O. V. Boetskaya, “Enthalpy of lanthanum germanide at 300–2012 K,” Poroshk. Metall., No. 5–6, 70–74 (1998).

  13. N. P. Gorbachuk and A. S. Bolgar, “Thermodynamic properties of NdSi1.8 and SmSi2 over a wide temperature range,” Powder Metall. Met. Ceram., 39, No. 11–12, 567–571 (2000).

    CAS  Google Scholar 

  14. V. N. Eremenko, Xiong Quoc Chi, Yu. I. Buyanov, and A. M. Khar’kova, “Lanthanum-germanium equilibrium diagram,” Dop. AN USSR, Ser. B, No. 9, 819–823 (1972).

  15. A. B. Gokhale and G. J. Abbaschin, “The Si-Sm (silicon-samarium) system,” in: Bull. Alloy Phase Diagr., 9, No. 5, 582–585 (1988).

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

__________

Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 3–4 (454), pp. 72–78, 2007.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Gorbachuk, N.P., Kirienko, S.N. Quantitative differential thermal analysis of polymorphic transformations in LaGe1.8 and SmSi2 . Powder Metall Met Ceram 46, 163–168 (2007). https://doi.org/10.1007/s11106-007-0026-4

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11106-007-0026-4

Keywords

Navigation