Size Effect in the Three-Dimensional Monte-Carlo Simulation of the Phase Separation Kinetics in Іsolated Particles
A. S. Shirinyan$^{1}$, Yu. S. Bilogorodskyy$^{1}$, V. A. Makara$^{1,2}$
$^{1}$Physicochemical Materials Science Centre of the Taras Shevchenko Kyiv National University and the National Academy of Science of Ukraine, 60 Volodymyrska Str., UA-01033 Kyiv, Ukraine
$^{2}$Taras Shevchenko National University of Kyiv, 60 Volodymyrska Str., UA-01033 Kyiv, Ukraine
Received: 28.02.2019; final version - 01.11.2019. Download: PDF
The work is devoted to identifying the size-dependent regularities of the formation and stabilization of a new phase in the process of temperature annealing of an isolated nanoscale particle of a metal alloy. On the basis of the computer model of the vacancy diffusion of atoms and the Monte-Carlo algorithm, an approach is proposed to determine the effect of limited material volume on the kinetics of phase separation in a particle with an inert shell. The developed complex software allows determining a significant range of characteristics, macroscopic, microscopic and energy parameters of the system: cluster sizes, nucleation energy, order parameters, diffusion coefficients, compositions and volumes of phases. The analysis of the kinetics of phase separation for initial supersaturations corresponding to unstable initial state of the alloy is performed. A size-dependent effect of slowing down kinetics of the formation of a new phase related to the reduction in the size of a nanosystem is revealed. A correlation between the particle size, phase separation rate and characteristics of phase transition is established. The approximation relations are given for the average volume of a new phase cluster, and the behaviour of the growth rate of new phase nuclei from the size of nanosystem, temperature and initial composition is investigated.
Key words: vacancy mechanism of diffusion, isolated nanoparticle, 3D Monte-Carlo simulation, new phase nucleus, size effect, phase separation, growth rate.
URL: http://mfint.imp.kiev.ua/en/abstract/v42/i01/0011.html
DOI: https://doi.org/10.15407/mfint.42.01.0011
PACS: 05.10.Ln, 61.46.-w, 64.60.an, 64.60.Q-, 64.75.Jk, 66.30.Pa, 81.07.Bc
Citation: A. S. Shirinyan, Yu. S. Bilogorodskyy, and V. A. Makara, Size Effect in the Three-Dimensional Monte-Carlo Simulation of the Phase Separation Kinetics in Іsolated Particles, Metallofiz. Noveishie Tekhnol., 42, No. 1: 11—32 (2020) (in Ukrainian)