Reliability of EAM potentials for FCC metals properties prediction
Abstract
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI--COLUMBIA AT REQUEST OF AUTHOR.] A perfectly transferable interatomic potential that works for different materials and systems of interest is lacking. This work considers the transferability of several existing interatomic potentials by evaluating their capability at various temperatures, to determine the range of accuracy of these potentials in atomistic simulations. A series of embedded-atom-method (EAM) based interatomic potentials has been examined for precious and popular metals in nanoscale studies. The potentials have been obtained from various credible and trusted repositories and were compared to tackle the lack of a comparison between several existing models. The interatomic potentials designed for the single elements, binary, trinary and higher order compounds were tested for each species using molecular dynamics simulation. Validity of results arising from each potential was investigated against experimental values at different temperatures from a temperature range around Debye temperature to melting point. The data covers accuracy of all studied potentials for prediction of the single crystals' elastic stiffness constants as well as the bulk, shear and Young's modulus of the polycrystalline specimens. As testing and benchmarking results for users is a necessity before running a new simulation, results of this work increase their assurance and lead them to the right model by a way to easily look up data. Referring to this work also prevents any inaccurate prediction by an atomistic simulation due to use of an inappropriate interatomic potential.
Degree
Ph. D.
Thesis Department
Rights
Access to files is limited to the University of Missouri--Columbia.