Propagation Length of Self-healing Slip Pulses at the Onset of Sliding: A Toy Model

Abstract

Macroscopic sliding between two solids is triggered by the propagation of a micro-slip front along thefrictional interface. In certain conditions, sliding is preceded by the propagation of aborted fronts, spanning only part of the contact interface. The selection of the characteristic size spanned by those so-called precursors remains poorly understood. Here, we introduce a 1D toy model of precursors between a slider and a track in which the fronts are quasi-static self-healing slip pulses. When the slider's thickness is large compared to the elastic correlation length and when the interfacial stiffness is small compared with the bulk stiffness, we provide an analytical solution for the length of the first precursor, Λ, and the shear stress field associated with it. These quantities are given as a function of the bulk material parameters, the frictional properties of the interface and the macroscopic loading conditions. Analytical results are in quantitative agreement with the numerical solution of the model. In contrast with previous models, our model predicts that Λ does not depend on the frictional breaking threshold of the interface. Our results should be relevant to the various systems in which self-healing slip pulses have been observed.

Onset of Sliding of Elastomer Multicontacts: Failure of a Model of Independent Asperities to Match Experiments

“…Such improved models may incorporate those tangential interactions in ways similar to models already developed for the normal interactions during normal loading of rough surfaces (see e.g. [3,25,26,7,8]).…”

Modeling and simulation in tribology across scales: An overview

“…These precursors manifest themselves at macroscale as a series of dents in the loading curve, indicating partial load relaxation [455]. The first models for the length of precursors were one-dimensional [442,[459][460][461][462][463]. Although the ad-hoc introduction of an initial shear stress field was improving the results [461], none of these models could be compared quantitatively with Fineberg's experiments, in which the height of the slider was not negligible.…”

Steady-state propagation speed of rupture fronts along one-dimensional frictional interfaces

“…after transients are finished. For the sake of simplicity and to enable analytical treatment, we use a 1D spring block model for the shear rupture of extended frictional interfaces, introduced in [12] to study the propagation length of precursors to sliding [9,[16][17][18][19][20]. Whereas the dynamics of multiple successive events in the macroscopic stickslip regime of this model was discussed in detail in [12], here we focus on the steady state propagation of a single rupture front.…”