State, rate and temperature–dependent sliding friction of elastomers

Abstract

We present an experimental investigation of the non stationary frictional properties of multicontact interfaces between rough elastomers and rough hard glass at low velocities (≤ 200 µm s −1 ). These systems, for which the deformation contribution to friction is negligible, are shown to exhibit a phenomenology which is similar to what is observed for non elastomeric materials in the same multi-contact configuration, and which are quantitatively described by the state-and rate-dependent friction laws. This permits to identify clearly the two contributions to adhesive friction which are mixed in steady sliding : the interfacial shear stress which appears as thermally activated formation and breaking of molecular bonds, and the real area of contact which evolves through viscoelastic creep of the load bearing asperities.

Theory of rubber friction: Nonstationary sliding

“…Recently Ronsin and Coeyrehourcq 18 have studied ͑experi-mentally͒ the state-, rate-, and temperature-dependent friction of elastomer, but focused mainly on the glassy side of the dynamical response of the polymer. An early study by Roberts and Thomas focused on some simple nonstationary sliding problems involving rubber.…”

Probing the micromechanics of a multi-contact interface at the onset of frictional sliding

“…For all runs, P was found to vary by less than 1% over the duration of the experiment and the apparent contact zone remains circular. The velocity v was chosen low enough for visco-elastic interfacial dissipation to be negligible [25]. Since the normal loading of the contact produces a significant shear force due to the small coupling between normal and lateral motion of each cantilever, the contact was manually renewed prior to each experiment, until the initial shear force Q was less than 1% of P .…”

Formation and development dynamics of femtosecond laser microplasma in gases

“…Several experiments on friction and on contact area as a function of the normal load find, with reasonable precision, that F ∝ A [15,16]. We note, however, that presumably the self-affine cutoff lengths ξ in these experiments are smaller than the length scales at which the experiments are performed -both Dieterich and Kilgore [15], and Ronsin and Coeyrehourcq [16] worked with polished surfaces.…”