2016/10/17 by M. I. Mendelev, T. L. Underwood, G. J. Ackland · 183 citations
Materials Science · Physics and Astronomy · #Atom (system on chip) #Diffusionless transformation #Embedded atom model #Interatomic potential #Martensite #Microstructure and mechanical properties #Molecular dynamics #Phase (matter) #Shape Memory Alloy Transformations #Titanium Alloys Microstructure and Properties #Transformation (genetics) #cond-mat.mtrl-sci
paper · pdf · doi:10.1063/1.4964654
published in The Journal of Chemical Physics 145(15), 154102 (American Institute of Physics)
openalex publication_date 2016/10/17 · openalex created_date 2016/10/28 · arxiv created 2016/12/09 · arxiv updated 2016/12/12 · openalex updated_date 2026/08/05
New interatomic potentials describing defects, plasticity, and high temperature phase transitions for Ti are presented. Fitting the martensitic hcp-bcc phase transformation temperature requires an efficient and accurate method to determine it. We apply a molecular dynamics method based on determination of the melting temperature of competing solid phases, and Gibbs-Helmholtz integration, and a lattice-switch Monte Carlo method: these agree on the hcp-bcc transformation temperatures to within 2 K. We were able to develop embedded atom potentials which give a good fit to either low or high temperature data, but not both. The first developed potential (Ti1) reproduces the hcp-bcc transformation and melting temperatures and is suitable for the simulation of phase transitions and bcc Ti. Two other potentials (Ti2 and Ti3) correctly describe defect properties and can be used to simulate plasticity or radiation damage in hcp Ti. The fact that a single embedded atom method potential cannot describe both low and high temperature phases may be attributed to neglect of electronic degrees of freedom, notably bcc has a much higher electronic entropy. A temperature-dependent potential obtained from the combination of potentials Ti1 and Ti2 may be used to simulate Ti properties at any temperature.