A stochastic model of stick-slip boundary friction with account for the deformation effect of the shear modulus of the lubricant.

The melting of an ultrathin lubricating film during the friction of two solid atomically smooth surfaces is studied within the limits of the Lorentz model that approximates a viscoelastic medium, the deformation effect of the shear modulus being taken into account. It is shown that the action of a random force representing additive non-correlated noise results in the sustained oscillation mode that corresponds to stickslip friction. The numerical modeling of the process yields the ratios between the relaxation times at which the stick-slip mode is characterized by a high amplitude. The amplitude of stick-slip transitions is found to decrease as the shear modulus of the lubricant increases. [ABSTRACT FROM AUTHOR]