Dynamic instability of the steady state of a planar front during non-equilibrium solidification of binary alloys

It is found that in temperature and concentration ranges where the solidus concentration increases with increasing solidification velocity, the steady state of the planar front is dynamically unstable. It is discussed how such a dynamic instability of the steady state of a solidifying planar front has an effect on its morphological stability. This is a possible explanation for the discrepancy between morphological stability theory and published experimental data (Hoglund et al., 1998) obtained from rapidly solidified Si-Sn melts.