Mechanical properties of Fe nanowires under uniaxial tests: a Molecular dynamic study

The present study aimed to evaluate the mechanical properties of BCC Fe nanowires, including their elastic moduli, ultimate strengths, stress-strain diagrams, and structural evolutions from BCC to FCC and HCP under external loading. For this purpose, the effects of temperature and various shapes of cross-sections (with the same area) on the mechanical properties of Fe nanowires are evaluated using molecular dynamics simulation. The well-known embedded atom method potential function is employed in Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) to model the metallic bonds between the Fe atoms. The Young's moduli are calculated based on the initial linear section of the stress-strain diagrams of uniaxial tension and compression of the nanowires. The comparison between the tensile and compressive results reveals that the strength values in compressive loading depend on the shapes of the cross-sections more than tensile loading following the order: circular> polygon> square> triangle. However, except for the triangular case, tensile strength values are less susceptible to the change of the cross-section shapes. On the other hand, for both loading states, increasing temperature results in reducing Young's moduli and ultimate strength values.

Keywords:

Nanowire , BCC , Molecular Dynamics , Tension , Compression