Liquid droplets migration in the solid phase of the dilute binary mixture in a directional solidification CBr4-C2Cl6

The behaviour of drops of liquid occurring in the solid phase of the dilute binary mixture CBr4C2Cl6 has been studied in terms of their rate of migrat ion in directional solidification experiments. The basic mechanism involved in this migration is the diffusion of the solute within the drops as a res ult of the concentration gradient which accompanies the temperature gradien t. These studies show that there is a correlation between this rate of migr ation and the Mullins-Sekerka threshold rate. Our results are compared with theoretical calculation based on the dynamic study of the recoil of the fr ont. (C) Academie des sciences/Elsevier, Paris.