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Influence of Thermal Treatment on Phase Formation Processes in Amorphous Alloys

  • Volodymir Lysov
  • Tatiana Tsaregradskaya
  • Oleg Turkov
  • Galina Saenko
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 210)

Abstract

The use of amorphous materials in current nanotechnology allows us to obtain characteristics that could not be produced using materials with crystalline structure. The metastable amorphous state obtained by ultrafast quenching does not always have the best characteristics, however, so devising methods of controlled nanostructuring is now an important area of metallic glass research. The great attention devoted to the processing (heat and pressure treatment) of amorphous alloys is due to their ability to acquire new properties in the nanocrystalline state. Amorphous alloys are heterogeneous systems with amorphous matrices and frozen-in crystallization centers that exist in the metastable state; their properties thus substantially depend on the influence of external conditions (e.g., temperature, pressure, isothermal exposure time), particularly upon phase transitions. Our statement of the problem results from the theory of amorphous alloy thermodynamic stability, according to which external effects (isothermal annealing or long exposure at room temperature) can substantially shift the phase equilibrium in a heterogeneous system with an amorphous matrix and frozen-in crystallization centers. The process of purification of the amorphous matrix from the frozen-in crystallization centers is theoretically substantiated and experimentally implemented, on the basis of the analysis of the positions of the thermodynamic theory of high-temperature stability of amorphous alloys. Аccording to which theory there is an interval of temperatures in which the difference of chemical potentials between phases in a heterogeneous system of the amorphous matrix – frozen-in crystallization centers are negative, that is, the condition for the dissolution of frozen-in crystallization centers is fulfilled. It is shown that the proposed heat treatment modes allow to expand the thermal stability of amorphous alloys on the basis of iron by 20–40 K by purifying the amorphous matrix from the frozen-in crystallization centers by means of upward diffusion. On the basis of the analysis of the theory of high-temperature thermodynamic stability of amorphous alloys, a method for obtaining an amorphous–nanostructural state from the initial amorphous is proposed.

Keywords

Amorphous alloys Crystallization High-temperature stability Frozen-in crystallization centers Upward diffusion 

References

  1. 1.
    Glezer АМ (2002) Ros Chym J. XLVI(5):57Google Scholar
  2. 2.
    Lysov VI, Tsaregradskaya TL, Turkov OV, Saenko GV (2013) J Phys Stud 7(2):2701.5Google Scholar
  3. 3.
    Ambrosimova HE (2011) Success Phys Sci 181(12)Google Scholar
  4. 4.
    Khar’kov EI, Lysov VI (1987) Rasplavy 1(1):30Google Scholar
  5. 5.
    Lysov VI, Tsaregradskaya TL, Turkov OV, Saenko GV (2014) Rus J Phys Chem A 88(12):2183–2187Google Scholar
  6. 6.
    Lysov VI, Tsaregradskaya TL, Turkov OV, Saenko GV (2017) Rus J Phys Chem A 91(12):2322–2226Google Scholar
  7. 7.
    Zaitsev AI, Zaytseva NE (2002) J Phys Chem 76(1)Google Scholar
  8. 8.
    Lysov VI, Tsaregradskaya TL, Turkov OV, Saenko GV (2007) Rus J Phys Chem V 81(10):1765Google Scholar
  9. 9.
    Novikov VN, Kharkov EI (1982) Phys Metals Metall 54(6):1210–1211Google Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Volodymir Lysov
    • 1
  • Tatiana Tsaregradskaya
    • 1
  • Oleg Turkov
    • 1
  • Galina Saenko
    • 1
  1. 1.Department of PhysicsTaras Shevchenko National University of KyivKyivUkraine

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