Polymorphic transformations in iodine titanium
Spivak L. V. 1, Kirchanov V. S.2, Shchepina N. E 3
1Perm State University, Perm, Russia
2Perm Research Polytechnic University, Perm, Russia
3Institute of Natural Sciences of Perm State University, Perm, Russia
Email: lspivak2@mail.ru, neshchepina@mail.ru

Based on the analysis of differential scanning calorimetry data, the possibility of classifying the observed endothermic or exothermic transformations as phase transformations of the first oder is considered. Two approaches have been implemented. The first is based on the correspondence between the temperatures of the maximum conversion rate and the temperatures of the extrema on the second derivative of the differential scanning calorimetry signal with respect to temperature. In the second approach, the phase transformation is considered as a kind of kinetic reaction of a chemical process with the determination of some parameters included in the kinetic equations. In this case, the order parameter of such reaction n is obtained from the analysis of the differential scanning calorimetry signal shape in the region of phase transformation registration temperatures. Using the example of experiments carried out during thermal cycling of titanium iodide samples, it is shown that both the first and second approaches make it possible to fairly adequately attribute the processes that cause calorimetric effects on the dependences of differential scanning calorimetry to first-order phase transitions. In particular, the obtained results of differential scanning calorimetry during heating and cooling of iodide titanium show that polymorphic transformations in it are realized by various mechanisms depending on the rate of thermal cycling and the thermal history of the metal. Keywords: activation energy, titanium, calorimetry, polymorphism, structure, approximation.
  1. Ya.S. Umansky, Yu.A. Skakov. Fizika metallov. Atomizdat, M.. (1978). 352 s. (in Russian)
  2. R. Abbaschian, L. Abbaschian, R.E. Reed-Hill. Physical Metallurgy: Principles. Cengage Learning (2009). 750 p
  3. G.N. Haidemenopoulos. Physical Metallurgy: Principles and Design. CRC Press --- Taylor and Francis (2018). 476 p. DOI: 10.1201/9781315211220
  4. L.V. Spivak, N.E. Shchepina. ZhTF 90, 7, 1145 (2020) (in Russian)
  5. L.V. Spivak, N.E. Shchepina. ZhTF 91, 8, 1233 (2021) (in Russian)
  6. L.V. Spivak, N.E. Shchepina. ZhTF 92, 4, 569 (2021) (in Russian)
  7. A.K. Kolmogorov. Izv. AN SSSR. Ser. Matematika. 1, 355 (1937) (in Russian)
  8. W. Wendlandt. Termicheskie metody analiza. Mir, M. (1978). 526 s. (in Russian)
  9. M. Avrami. ZhKhF 7, 12, 1103 (1939) (in Russian). DOI: 10.1063/1.1750380
  10. J. v Sestak. Thermophysical Properties of Solids. Measurments. Their Theoretical Thermal Analysis. Academia Prague (1984). 456 p
  11. A.K. Galwey, M.E. Brown. Handbook of Thermal Analysis and Calorimetry V. 1: Principles and Practice / Ed. M.E. Brown. Elsevier Science B. V. (1998). P. 147
  12. Introduction to thermal analysis / Ed. M.E. Brown. Kliwer Academic Publishers. N.Y., Boston, Dordricht, London, Moscow (2001). 264 p
  13. H.E. Kisinger. Anal. Chem. 29, 11, 1702 (1957). DOI: 10.1021/ac60131a045
  14. S. Vyazovkin, A.K. Burnham, J.M. Criado, L.A. Perez-Maqueda, C. Popescu, N. Sbirrazzuoli. Thermochim. Acta 520, 1--2, 1--19 (2011). DOI: 10.1016/j.tca.2011.03.034
  15. I.L. Knunyants. Kratkaya khimicheskaya entsikloperiya. Ripol Klassik, M. (2013). T. 4. 596 s. (in Russian)
  16. S.M. Sarge, G.W.H. Hohne, W.F. Hemminger. Calorimetry. Fundamentals Instrumentation and Applications. Wiley-VCH Verlag GmbH \& Co. KGaA: Weinheim, Germany (2014). 304 p

Подсчитывается количество просмотров абстрактов ("html" на диаграммах) и полных версий статей ("pdf"). Просмотры с одинаковых IP-адресов засчитываются, если происходят с интервалом не менее 2-х часов.

Дата начала обработки статистических данных - 27 января 2016 г.


Ioffe Institute

Institute Officers:

Director: Sergei V. Ivanov

Contact us:

26 Polytekhnicheskaya, Saint Petersburg 194021, Russian Federation
Fax: +7 (812) 297 1017
Phone: +7 (812) 297 2245
E-mail: post@mail.ioffe.ru