Effects of Nonstationarity During Directional Crystallization of Binary System in Quasi-Two-Dimensional Specimen
O. P. Fedorov$^{1,2}$, V. F. Demchenko$^{1,3}$, Ye. L. Zhivolub$^{2}$
$^{1}$Space Research Institute, NAS of Ukraine and State Space Agency of Ukraine, 40, 4/1, Academician Glushkov Ave., UA-03187 Kyiv, Ukraine
$^{2}$G.V. Kurdyumov Institute for Metal Physics, NAS of Ukraine, 36 Academician Vernadsky Blvd., UA-03142 Kyiv, Ukraine
$^{3}$E. O. Paton Electric Welding Institute, NAS of Ukraine, 11 Kazymyr Malevych Str., UA-03142 Kyiv, Ukraine
Received: 11.07.2014. Download: PDF
By the methods of direct observation of crystallization front and relevant simulation, the problem of stationarity of the phase boundary motion during directional solidification is investigated. Transparent metal-like system (succinonitrile—acetone) is used; the solution of non-stationary thermal and diffusion problem is obtained for the conditions corresponding to the experiment. Both the direct observation and the simulation show that advancement of the plane phase boundary under typical growing conditions is essentially nonstationary. Continuous displacement of the position of the phase boundary towards an isotherm is observed in accordance with calculated impurity accumulation dynamics in front of the phase boundary. Due to effects of nonstationary growth under typical experimental conditions, the parameters of stability of crystallization front depend on time of observation. It substantially constrains an applicability of the linear theory of stability of the crystallization front.
Key words: nonstationarity, phase boundary, crystallization front, succinonitrile, mathematical simulation, linear theory of stability.
URL: http://mfint.imp.kiev.ua/en/abstract/v37/i02/0185.html
DOI: https://doi.org/10.15407/mfint.37.02.0185
PACS: 02.60.Cb, 02.60.Lj, 64.70.dg, 81.10.Aj, 81.10.Fq, 81.10.Mx, 81.30.Fb
Citation: O. P. Fedorov, V. F. Demchenko, and Ye. L. Zhivolub, Effects of Nonstationarity During Directional Crystallization of Binary System in Quasi-Two-Dimensional Specimen, Metallofiz. Noveishie Tekhnol., 37, No. 2: 185—198 (2015) (in Russian)