Abstract
The transformation kinetics for a system undergoing classical nucleation and growth are described. Growth velocity anisotropy is allowed which causes non-spherical particle morphologies. The present derivation solves for the transformation rate if these anisotropic particles are randomly distributed and randomly oriented in space, in contrast to earlier derivations. Three specific derivations are examined which cover both 2D and 3D spaces and both instantaneous and continuous nucleation. Although the expressions that are developed for randomly oriented anisotropic particles are the same as the traditional Johnson—Mehl—Avrami—Kolmogorov (JMAK) expressions, the restriction that the orientation of particles are cooperatively aligned is lifted. The results are discussed within the framework of practical limitations imposed by the basic JMAK derivation conditions.