Kinetic effect of crystal growth on the absolute stability of a planar interface in undercooled melts

The stability of a planar interface during the non-equilibrium solidification of undercooled melts is reexamined by the linear stability theory of Mullins and Sekerka. The incorporation of the kinetic coefficient, which is dependent on the local interfacial temperature, into the analysis leads to a striking change of the absolute stability criterion proposed by Trivedi and Kurz. It is also shown that whether the absolute stability of a planar interface exists relies on a dimensionless parameter q which is a function of the physical properties of the melts. Only the melts whose q is smaller than 1 can solidify into a stable planar interface when the crystal growth velocity exceeds the critical value.