|About this Abstract
||Materials Science & Technology 2019
||Phase Transformations in Ceramics: Science and Applications
||Prediction of Diffusionless Phase Transformation by Determination of the Orientation Relationship, Shear, and Motif Translation with the Smallest Atom Shuffles
||Randall Hay, Emmanuel Boakye, Pavel Mogilevsky, Thomas Key
|On-Site Speaker (Planned)
A crystallographic model to predict diffusionless phase transformations has been developed. If atom shuffles for an orientation relationship (OR) and motif translation between phases related by shear are small, the transformation is diffusionless. Lattices common to both phases related by either shear along a “near” invariant plane or line are determined and ranked by strain to coincidence, shear magnitude, and number of primitive lattices in the coincidence lattice (Σ). Algorithms and assumptions that minimize the large number of calculations are described. Atom shuffles required to form the daughter phase after shear are calculated for 8<sup>3<sup> motif translations in units of 1/8 the length of each coincidence lattice vector. The translation with the smallest shuffles is determined. ORs are ranked by shuffle distance and strain to coincidence. Typically small shuffles are only found for ORs with low Σ. Application to phase transformations in rare earth disilicates is described and discussed.
||Definite: At-meeting proceedings