Molecular-Dynamics Modeling of the Surface Mechanical Properties Using the ReaxFF Potential

• Published in: Surface investigation, x-ray, synchrotron and neutron techniques x-ray, synchrotron and neutron techniques, 2021-12, Vol.15 (Suppl 1), p.S92-S97
• Main Authors: Rusalev, Yu. V., Guda, A. A., Pashkov, D. M., Belyak, O. A., Kolesnikov, V. I., Soldatov, A. V.
• Format: Article
• Language: English
• Subjects: Amorphization; Chemistry and Materials Science; Crystal defects; Crystal dislocations; Crystallites; Deformation; Degree of crystallinity; Density functional theory; Dynamic mechanical properties; Irreversible processes; Material properties; Materials Science; Mathematical models; Mechanical properties; Molecular dynamics; Nanoindentation; Point defects; Surface roughness; Surfaces and Interfaces; Thin Films; Tribology; Wear resistance
• ISSN: 1027-4510; 1819-7094
• DOI: 10.1134/S1027451022020185

The tribological and wear-resistant behavior of a surface are determined by its morphology, level of defects, degree of crystallinity, and mechanical properties. The surface roughness, crystallite size, dislocations, and point defects are significant parameters on different spatial scales. Advances in methods for supercomputer modeling enable numerical experiments on the atomic level as well as at the nanoscale and microscale. Here, we perform nanoindentation experiments for a system consisting of ~1000 particles, which is the level where precise methods of density functional theory are no longer applicable while empirical potentials are decidedly rough. Defect-formation processes, effects of amorphization on mechanical properties, and irreversible processes of material deformation caused by an indenter are demonstrated at the scale of 2.5 nm. Our results open up new avenues for studying the mechanical and tribological properties of materials by numerical simulations of nanoindentation.