ABSTRACT

The first experimental inquiry into the role of the thermal factors on the capture of particles by an advancing crystallization front was carried out in 1973 by Zubko et al. [9]. Their experiments revealed that the interaction between a particle and the solidifying interface depended primarily on the relative magnitudes of the coefficients of thermal conductivity of the particle, k_p, and that of the melt, k_l; namely the particle is captured if k_p > k_l and rejected by the solid front if k_p < k_l regardless of the wetting properties of the particle. We refer to these experiments as the thermal puzzle. Numerous attempts have been put forth to explain these experimental findings. In this paper we review the concept of thermal force that was brought to light recently by Hadji [15, 16] to explain the thermal puzzle. The derivation of the thermal force is revisited to include the particle’s solubility effects. In addition, results of an investigation of the influence of the thermal factors on the stability of the solid-liquid interface are also presented.