Molecular dynamics simulation of mechanical properties of hafnium nanowires: the effects of size, temperature and strain rate

Abstract

Molecular dynamics simulations on single crystalline hafnium nanowires are carried out to investigate their mechanical behavior under uniaxial tension. This study is done with the use of Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) in which a modified embedded atomic method is employed for calculation of all interatomic forces. The effects of size, temperature, and strain rate on the elastic and failure behavior of nanowires are studied. Several cases within various diameters and lengths (10-100 Å) are subjected to uniaxial tensile with various rates (0.0001–0.01 ${ps}^{-1}$) of deformation. In order to investigate the effects of temperature on the mechanical behavior of nanowires, simulations are performed at four values (1K, 300K, 500K, and 700 K) of temperature. The results reveal that in higher values of aspect ratio, nanowires become stiffer, but their ductility declines. Decrease in their temperature also leads to the same consequences. Furthermore, faster deformations are found to be responded by nanowires showing with growth in both sustainability and ductility.