Effect of temperature and velocity on deformation behavior and frictional properties of rough surface at the nanoscale

Context

Soft materials, such as gold, play a crucial role in solid-state devices for the electronics industry, biochemical sensors, and miniaturized medical machinery. This study investigates the abrasive behavior and friction properties of the rough surface of polycrystalline Au material through a shearing process using molecular dynamics (MD). The effects of friction velocity and temperature are explored by analyzing the force–time curve, crystal evolution, shear strain distribution, differential distribution, and atomic flow direction. Temperature affects polycrystalline Au more deeply; almost crescent-peak regions of Au transform into an amorphous structure upon contact with abrasive Ni at shearing temperatures of 450 and 600 K, while atoms vibrate around their equilibrium positions. The compress simulation shows the different behavior of the Au material under various potentials. At lower abrasive velocities, atomic movement and the deformation region are more pronounced. The normal force increases with an increase in abrasive velocity from 20 to 100 m/s or a temperature rise from 150 to 450 K; however, it decreases as the abrasive velocity reaches 150 m/s or when the temperature increases to 600 K.

Methods

The ATOMSK program is applied to create the polycrystalline Au and Ni structures. The MD method is employed to investigate the influence of various friction velocities and temperatures on the force–time curve, crystal evolution, shear strain distribution, differential distribution, and atomic flow direction of polycrystalline Au alloys. The simulation process is performed via LAMMPS software. The visualization tool (OVITO) is borrowed to examine, evaluate, and demonstrate the simulation results. The Morse potential is used to describe the interaction forces between Ni–Ni, Au–Au, and Ni-Au.