论文标题
稳定滑动时接触软表面的动力测量：固定深入摩擦学
Dynamical force measurements for contacting soft surfaces upon steady sliding: Fixed-depth tribology
论文作者
论文摘要
表面之间的摩擦学可以对机械系统的响应产生深远的影响，例如颗粒颗粒如何驱动到流动。在这项工作中，我们执行实验，以溶解两个半圆柱形PDM（聚二甲基硅氧烷）样品之间的力的切向成分，因为它们在一系列受控速度的范围内相互滑动。时间平均的摩擦力显示了四十年来对滑动速度的非单调依赖性，这与范式的Stribeck图和与之相关的三个动力学制度一致。我们专门设计的固定深度设置使我们能够研究力在其中一个方案中表现出强粘液模式的力的波动。重复实验的数据表明，在我们的实验过程中，板条滑移模式的“发作速度”及其沿样本变化的空间位置逐渐变化，表明样品表面的变化。此外，我们通过使用彼此摩擦的球形样品进行对应实验，以直接连接颗粒间摩擦学与我们先前工作中报道的颗粒流量[Phys。莱特牧师。 126,128001（2021）]。
The tribology between surfaces can have a profound impact on the response of a mechanical system, such as how granular particles are driven to flow. In this work, we perform experiments that time-resolve the tangential and normal components of the force between two semi-cylindrical PDMS (polydimethylsiloxane) samples immersed in fluid, as they slide against each other in a range of controlled speeds. The time-averaged friction force shows a non-monotonic dependence on the sliding speed over four decades, which is consistent to the paradigmatic Stribeck diagram and three dynamical regimes associated with it. Our specially designed fixed-depth setup allows us to study the fluctuation of force that exhibits strong stick-slip patterns in one of the regimes. Data from repetitive experiments reveal that both the "onset speed" for the stick-slip patterns and its spatial location along the sample change gradually during the course of our experiments, indicating changes on the sample surfaces. In addition, we conduct counterpart experiments by using spherical samples rubbing against each other, to make a direct connection of the inter-particle tribology to the granular flow reported in our previous work [Phys. Rev. Lett. 126,128001 (2021)].
