|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Interface-driven Phenomena in Solids: Thermodynamics, Kinetics and Chemistry
||Molecular Dynamics Simulation of B2-B33 Transformation in Ni-Zr Alloy
||Seth R Wilson, Mikhail Mendelev
|On-Site Speaker (Planned)
It is widely accepted that the presence of solutes slows down interface migration. We will report an interesting example in which solutes instead increase interface velocity. Recently, high-energy x-ray diffraction measurements of electrostatically levitated equimolar Ni-Zr liquid droplets demonstrated that the solidification pathway proceeds through the nucleation and growth of the metastable B2 phase, which persists for several seconds before the appearance of the stable B33 phase. The transformation between two stoichiometric compounds of the same composition provides a fascinating opportunity to study the influence of solutes on interface migration. To simulate the effect of solutes we increased the Zr content in a thin layer near the initial interface position. Molecular dynamics simulation demonstrated that the resulting steady state drags a small number of excess Zr atoms, and that this motion is characterized by a higher velocity than an interface without excess Zr, in contrast to traditional solute drag models.
||Planned: A print-only volume