Homogeneous nucleation via atomic density fluctuations in undercooled liquid metals

Abstract

A new mechanism is proposed for homogeneous nucleation of crystalline phases via density fluctuations in undercooled melts. This process leads to the formation of crystalline nuclei of the critical size by a diffusionless transformation during relaxation of density fluctuations in the undercooled liquid. The proposed mechanism avoids the postulation of a distribution of energetically unfavourable sub-critical nuclei, as was required by earlier formulations.