TRANSFORMATION KINETICS FOR RANDOMLY ORIENTED ANISOTROPIC PARTICLES

The transformation kinetics for a system undergoing classical nucleati on and growth are described: Growth velocity anisotropy is allowed whi ch 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 ea rlier derivations. Three specific derivations are examined which cover both 2D and 3D spaces and both instantaneous and continuous nucleatio n. Although the expressions that are developed for randomly oriented a nisotropic particles are the same as the traditional Johnson-Mehl-Avra mi-Kolmogorov (JMAK) expressions, the restriction that the orientation of particles are cooperatively aligned is lifted. The results are dis cussed within the framework of practical limitations imposed by the ba sic JMAK derivation conditions.