Avrami exponents for transformations producing anisotropic particles

Authors: Weinberg, Michael C.; Birnie, Dunbar P. III
Source: Journal of Non-Crystalline Solids 202 (1996)  290-296.

Abstract: The behavior of Avrami exponents (AE) for systems which produce anisotropic particles (for which shielding effects and phantoms occur) is examined. Probabilistic arguments used in previous studies are applied to derive expressions for the AE as a function of time or the extent of transformation. Numerical calculations for the one dimensional (1D) cases of site saturation and continuous nucleation show that blocking effects produce a minimum in plots of AE versus extent of transformation. The influence of growth rate anisotropy upon the magnitude of the reduction in the AE is also examined and certain features of the behavior of the AE for 2D and 3D systems are discussed.