Frictional interfaces are abundant in natural and manmade systems and their dynamics still pose challenges of fundamental and technological importance. A recent extensive compilation of multiple-source experimental data has revealed that velocity-strengthening friction, where the steady-state frictional resistance increases with sliding velocity over some range, is a generic feature of such interfaces. Moreover, velocity-strengthening friction has very recently been linked to slow laboratory earthquakes and stick-slip motion. Here we elucidate the importance of velocity-strengthening friction by theoretically studying three variants of a realistic rate-and-state friction model. All variants feature identical logarithmic velocity-weakening friction at small sliding velocities, but differ in their higher velocity behaviors. By quantifying energy partition (e.g. radiation and dissipation), the selection of interfacial rupture fronts and rupture arrest, we show that the presence or absence of velocity-strengthening friction can significantly affect the global interfacial resistance and the total energy released during frictional instabilities ("event magnitude"). Furthermore, we show that different forms of velocity-strengthening friction (e.g. logarithmic vs. linear) may result in events of similar magnitude, yet with dramatically different dissipation and radiation rates. This happens because the events are mediated by interfacial rupture fronts with vastly different propagation velocities, where stronger velocity-strengthening friction promotes slower rupture. These theoretical results may have significant implications on our understanding of frictional dynamics.
Zhejiang University（浙江大学）；Tsinghua University（清华大学）；International School for Advanced Studies (SISSA)（高级研究国际学院）；International Centre for Theoretical Physics (ICTP)（理论物理国际中心）；Nanjing University of Aeronautics and Astronautics（南京航空航天大学）；Tsinghua Shenzhen International Graduate School, Tsinghua University（清华大学深圳国际研究生院）；Institute of Superlubricity Technology, Research Institute of Tsinghua University in Shenzhen（清华大学深圳研究院超滑技术研究所）
Granite sliding on granite: friction, wear rates, surface topography, and the scale-dependence of rate-state effects
Saarland University（萨尔兰大学）；Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences（中国科学院兰州化学物理研究所）；Peter Grünberg Institute (PGI-1), Forschungszentrum Jülich（于利希研究中心彼得·格林贝格研究所（PGI-1））；MultiscaleConsulting（多尺度咨询公司）
Do uniform tangential interfacial stresses affect adhesion?
我们提出的理论论据，线弹性和热力学的基础上，表明在滑动粘合剂接触的界面切向应力不影响在所有的系统，然后遵循经典的JKR解决方案的粘合剂行为。我们的发现解释了Vorvolakos和Chaudhury在2003年的实验观察，他们发现PDMS球的接触面积在滑动过程中保持恒定，并且与JKR解决方案一致，至少达到1 mm/s的速度，以及Carpick等人的Carpick，他观察到，在超真空（UHV）中，镀铂原子力显微镜（AFM）针尖与云母表面之间的摩擦力与Johnson-Kendall-Roberts（JKR）预测的接触面积成比例地随载荷变化。我们表明，减少的接触面积，实验观察到在较高的滑动速度，可以引起的粘合剂粘结的密度的减少，作为速度的增加，或引起的排斥能量项与应力的空间波动在界面处。这可以解释为什么在相对大的滑动速度下粘附被完全掩盖。此版本的文件遵循勘误表的出版：Nicola Menga，Giuseppe Carbone，Daniele Dini：勘误表“均匀的切向界面应力是否会增强粘附力？“[Journal of the Mechanics and Physics of Solids 112（2018）145--156]，Journal of the Mechanics and Physics of Solids，133，103744，https：//doi.org/10.1016/…
