Development Stages of the Cluster-Coagulation Model of Supercooled Metals Crystallization
Abstract: The paper analyzes the successive stages of crystallization during cooling of metal melts: clustering, nucleating, nucleus coagulation and mass solidification. The step listed are analyzed on the basis of cooling thermograms that cover both temperatures above and below the melting point (that is areas overheating and undercooling of melts). As a result of such studies, the following patterns were identified: a rapid transition from quasi-equilibrium crystallization with a practical absence of supercooling to non-equilibrium-explosive with significant supercooling; It is established that this effect is associated with a certain critical heating of the liquid phase; mean supercooling does not depend on a further increase in the heating of the melt above the critical temperature; The temperature range of the existence of clusters is related to the mesophase. The dependence equations of the Gibbs energy on temperature corresponding to each stage are derived. A scheme has been developed for the change in enthalpy of each crystallization stage. Results are consistent with the main provisions of the cluster-coagulation model of melt crystallization.
Keywords: melt, overheating, overcooling, clustering, nucleation, coagulation, crystal nuclei, crystallization, order parameter, Gibbs energy, enthalpy, nucleation work, crystallinity degree.
Pages: 5-15.
For citation:
For citation: Aleksandrov, V. D.; Frolova, S. A.; Zozulia, A. P. Development Stages of the Cluster-Coagulation Model of Supercooled Metals Crystallization. – Text : electronic. – In: <em>Metal Constructions</em>. – 2019. – Vol. 25, N 1. – Р. 5-15. – URL: https://donnasa.ru/publish_house/journals/mk/2019-1/01_aleksandrov_frolova_zozulia.pdf (date of access: 18.12.2024). – ISSN 1993-3517.
Vol. 25, N 1 (2019)
Journal: Metal Constructions
Publish house: Donbas National Academy of Civil Engineering and Architecture
Journal: Metal Constructions
Publish house: Donbas National Academy of Civil Engineering and Architecture