Rate and state variable friction laws: Estimation of model parameters for slip velocity dependence at coseismic slip rates

In the present study plate-impact pressure-shear friction experiments are conducted to study dynamics of high-speed slip at metal-on-metal interfaces. By using a CH tool-steel/Ti–6Al–4V tribo-pair and appropriate selection of the flyer and target plate thicknesses, the experiment has been used to investigate the frictional resistance of sliding interfaces subjected to step changes in slip rates. In order to describe the frictional memory effects a model based on Ruina–Dieterich slip law has been utilized. It is noted that the model parameter a in the range of 0.01–0.25 with characteristic lengths of L=5–7 m provides a reasonably good fit to the experimental data. © 2009 American Institute of Physics. doi:10.1063/1.3259395