Molecular Origin of Limiting Shear Stress of Elastohydrodynamic Lubrication Oil Film Studied by Molecular Dynamics
نویسندگان
چکیده
All-atom molecular dynamics simulations of an elastohydrodynamic lubrication oil film are performed to study the effect of pressure. Fluid molecules of n-hexane are confined between two solid plates under a constant normal force of 0.1–8.0 GPa. Traction simulations are performed by applying relative sliding motion to the solid plates. A transition in the traction behavior is observed around 0.5–2.0 GPa, which corresponds to the viscoelastic region to the plastic–elastic region, which are experimentally observed. This phase transition is related to the suppression of the fluctuation in molecular motion.
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