HOMOGENEOUS CRYSTALLINE NUCLEATION VIA ATOMIC DENSITY-FLUCTUATIONS INTHE LIQUID-STATE - APPLICATIONS

It is demonstrated that homogeneous nucleation may be initiated in ato mic density fluctuations within the undercooled liquid. Density fluctu ations of appropriate amplitude, corresponding to the change of the at omic density upon crystallization at the nucleation temperature T(N), allow fast diffusionless nucleation up to a subcritical-size embryo wh ose size may be close to that of the classical critical nucleus, depen ding on the change in the atomic volume upon crystallization at T(N). A Monte Carlo simulation, allowing the effect of the increased atomic density of the undercooled liquid on the interfacial energy to be eval uated, supports applications to Al and Ni. It becomes thus possible to quantify the contribution of a presumed diffusionless nucleation path in connection with the liquid atomic density at T(N).