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Nucleation and growth of second phase precipitates under non-isothermal conditions

A. R. Massih·L. O. Jernkvist
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Abstract

The Langer-Schwartz equations for precipitation are formulated to calculate nucleation, growth and coarsening of second phase precipitates under non-isothermal situations. A field-theoretic steady-state nucleation rate model is used in the analysis. The field-theoretic nucleation rate is compared with the classical nucleation rate relation derived from the Fokker-Planck equation. This integrated model is used to simulate a bcc-to-hcp phase quenching and subsequent annealing in the hcp phase of a dilute zirconium alloy, where the mean precipitate size, number density and the degree of supersaturation are calculated as a function of time. The influence of cooling rate on the aforementioned parameters is evaluated. A lower cooling rate results in larger precipitates with a smaller number density in concordance with observations.

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A. R. Massih, L. O. Jernkvist. 2005-11-08. Nucleation and growth of second phase precipitates under non-isothermal conditions. https://arxiv.org/abs/cond-mat/0511201

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