Validity of effective medium theory for aluminium under tension

摘要

Reliability of the potential functions under the condition far from equilibrium states, which is called transferability, is an important factor in the simulations of materials with nanoscopic complex structure under high stress condition. However, it has not been sufficiently investigated because it is difficult to get precise experimental data in such conditions. In this paper, simulations are conducted for aluminium bulk, grain boundary of aluminium and atomic chain under high strain using the potential function of the effective medium theory (EMT) as well as ab initio calculations in order to clarify the validity of EMT. In the cases of single crystal and the grain boundary under tensile strain, the results obtained from the EMT potential agree well with those obtained by ab initio analysis. However, the EMT cannot be applied to the atomic chain because the distribution of charge density differs significantly from that in the bulk. [References: 20]