Comparative analysis of models for solute trapping in rapid solidification

Abstract

Phase-field models (WBM- and EFKP-model [1,2]) are extended in the present work to rapid solidification in which local non-equilibrium phenomena occur in bulk phases and within the diffuse solid-liquid interface. The extended model is developed using a thermodynamic approach to fast phase transitions within a diffuse interface in a binary system [3]. We investigate solute trapping, which has been introduced to define the processes of non-equilibrium solute redistribution at the solid-liquid interface. The solute trapping effect in solidifying binary melts is compared with previous sharp-interface models and using the present extensions of WBM- and EFKP- phase-field models. This work is supported by RFBR Nos. 08-02-91957NNIO_a, 09- 02-12110-ofi-m; ROSNAUKA No. 2009-1.5-507-007-002; DAAD No. A/08/81583; DFG No. HE 1601/19; DLR Agency under contract number 50WM0736. [1] A.A. Wheeler, W.J. Boettinger, G.B. McFadden: Phys. Rev. E 47 (1993) 1893. [2] B. Echebaria, R. Folch, A. Karma, M. Plapp: Phys. Rev. E 70 (2004) 061604. [3] P. Galenko, D. Jou: Phys. Rev. E 71 (2005) 046125.