Molecular dynamics modelling and simulation of mechanical nanoscratching of polystyrene

Fundamental understanding of the nanomechanical machining mechanisms of polystyrene using molecular dynamics simulations is of significant importance for fabricating the polystyrene pellet used for the inertial confinement fusion fast heating. In current work a three-dimensional molecular dynamics model of nanoscratching of amorphous polystyrene is established based on the full atomistic polystyrene model and the AIREBO potential. Subsequent molecular dynamics simulation using the as-established model demonstrates that the equilibration configuration of the simulated system can be achieved by energy minimisation and following NPT relaxation in the relaxation process. In the following scratching process accompanied with material removal, scratching force, normal force and lateral force vary accurately upon different stress states applied by the probe. The research results indicate that the as-established MD model possesses high accuracy to characterise the mechanical response and deformation behaviour of polystyrene under nanoscratching.