Duarte M, Vragovic I, Molina J M, Prieto R, Narciso J, Louis E
Departamento de Física Aplicada and Instituto Universitario de Materiales, Universidad de Alicante, San Vicente del Raspeig, 03690 Alicante, Spain.
Phys Rev Lett. 2009 Jan 30;102(4):045501. doi: 10.1103/PhysRevLett.102.045501. Epub 2009 Jan 28.
It has been shown that the friction force time series in sliding friction under wear conditions is self-similar and has a 1/f power spectrum. Albeit a variety of models, mostly inspired in the field of earthquakes, has been explored, an important factor was overlooked: the role of debris. This Letter describes sliding friction experiments on steel with alumina pins, carried out with and without debris blowing, that prove the role of loose debris in determining the 1/f character of the friction force. A damped-forced harmonic oscillator with two friction terms, one purely random and another inversely proportional to the amount of loose debris, calculated by means of a modified sandpile model, is proposed to describe the dynamics of friction under wear conditions.
研究表明，磨损条件下滑动摩擦中的摩擦力时间序列是自相似的，具有1/f功率谱。尽管已经探索了多种主要受地震领域启发的模型，但一个重要因素被忽视了：碎屑的作用。本信函描述了在有和没有碎屑吹拂的情况下，用氧化铝销对钢进行的滑动摩擦实验，这些实验证明了松散碎屑在确定摩擦力的1/f特性方面的作用。通过修正的沙堆模型计算，提出了一个具有两个摩擦项的阻尼受迫谐振子，其中一个是纯随机的，另一个与松散碎屑的量成反比，以描述磨损条件下的摩擦动力学。
