Dynamic mechanical contact behaviours of amorphous nanoparticles subjected to high-speed impact

The dynamic mechanical contact behaviours between nanoparticles, are of importance for designing advanced nanodevices. In this work, dynamic mechanical response between amorphous nanospheres has been probed by using fully atomistic molecular dynamics simulations. We confirm that the contact radius is greater than Hertzian predictions and the correlation between contact radius and number of atoms in contact still obeys linear relationship largely. It has been discovered that typical yield strength σ-Young's modulusE₀ relationship (σ = E₀/10) still holds for amorphous carbon nanospheres. Contact radius is characteristics of staircase-shaped hike with increasing normal displacement, but the magnitude of contact radius is prone to approach the Hertzian prediction with increasing the particle size. At the atomic level, the correlation between contact radius and number of contacting atoms exhibits weak dependence on particle size for small-sized nanoparticles, but for large-sized particles the number of contacting atoms plays dominant role in governing the contact radius.