Warning! Note that elemental potentials taken from alloy descriptions may not work well for the pure species. This is particularly true if the elements were fit for compounds instead of being optimized separately. As with all interatomic potentials, please check to make sure that the performance is adequate for your problem.
Citation: V. Borovikov, M.I. Mendelev, and A.H. King (2016), "Effects of stable and unstable stacking fault energy on dislocation nucleation in nano-crystalline metals", Modelling and Simulation in Materials Science and Engineering, 24(8), 085017. DOI: 10.1088/0965-0393/24/8/085017.
Abstract: Dislocation nucleation from grain boundaries (GB) can control plastic deformation in nano-crystalline metals under certain conditions, but little is known about what controls dislocation nucleation, because when data from different materials are compared, the variations of many interacting properties tend to obscure the effects of any single property. In this study, we seek clarification by applying a unique capability of semi-empirical potentials in molecular dynamics simulations: the potentials can be modified such that all significant material properties but one, are kept constant. Using a set of potentials developed to isolate the effects of stacking fault energy, we show that for a given grain boundary, loading orientation and strain rate, the yield stress depends linearly on both the stable and unstable stacking fault energies. The coefficients of proportionality depend on the GB structure and the value of the yield stress is related to the density of the E structural units in the GB. While the impact of the stable stacking fault energy is easy to understand, the unstable stacking fault energy requires more elucidation and we provide a framework for understanding how it affects the nucleation and propagation process.
Notes: This listing is for the MCu34 parameterization listed in the reference. Dr. M.I. Mendelev (Ames Laboratory) noted that these are new fictional potentials intended to supplement the existing potentials posted to the NIST repository (as the 2015--Borovikov-V-Mendelev-M-I-King-A-H-LeSar-R--fictional-Cu-# listings). Dr. Mendelev further noted that, "the new potentials provide the same SFE as 2013--Mendelev-M-I-King-A-H--Cu but different unstable stacking fault energy (USFE). All these Cu fictional potentials are designed to study the effect of SFE and USFE on the deformation behavior in fcc metals." Reference information added March 5, 2020.
See Computed Properties Notes: This file was sent by M.I. Mendelev (Ames Laboratory) on 19 Aug. 2015 and posted with his permission. Update 19 July 2021: The contact email in the file's header has been changed. Update Jan 14 2022: Citation information has been updated in the file's header. File(s):