The Formation and Stability of Nanosphere Composites

Abstract

The nucleation of spherical particles forms an interesting study on new nano composites. If smaller, disperse particles are desired, tuning of parameters becomes necessary. According to classical teachings, a critical radius exists for “homogenous” nucleation. This thermodynamic approach needs to be reconciled with the heat transfer balances dictated by rate parameters and boundary conditions, which are absent in the former approach The reconciliation of the two can be attempted by examining the moving boundary problem and its solution which depends on the phase transformation parameters, the heat transfer coefficients and the “under cooling” or thermal driving force dependent on the boundary and initial conditions. Without going into abstract mathematical arguments, a stable moving interface can be expressed as a function of time and radius and hence the two approaches can be connected where the radial growth is expressed as a power of time—a quasi steady state solution is obtainable.