(a)觸發局部滑移所需的最大力 與 (b) 不同掃描速率下的滑移長度的分布。
介觀尺度的黏滑摩擦統計定律
Nature Communications 14, 6221
Caishan Yan, Hsuan-Yi Chen, Pik-Yin Lai & Penger Tong
Statistical laws of stick-slip friction at mesoscale
我們透過一組通用的雪崩動力學統計定律來描述黏滑摩擦。例如，觸發局部滑移所需的最大力服從廣義極值分佈，而滑移長度則透過冪律分佈很好地表徵，並解釋了冪律指數。此外，掃描探頭的黏滑運動可以想像為其質心在隨機釘扎場中移動的結果，該隨機釘扎力場由受到布朗相關釘扎力場的欠阻尼彈簧塊模型描述。本模型捕捉了黏滑摩擦的基本物理原理，為黏滑摩擦中的雪崩動力學提供了長期尋求的物理機制。
We demonstrated that stick-slip friction can be described by a common set of statistical laws of avalanche dynamics. The force needed to trigger the local slips obeys the generalized extreme value distribution, whereas the slip lengths are well-characterized by a power-law distribution with the power-law exponent explained as a result of the center-of-mass of a block moving in a random pinning force field described by an under-damped spring-block model subjected to a Brownian-correlated pinning force field. This model captures the essential physics of the stick-slip friction at mesoscale, providing a long-sought physical mechanism for the avalanche dynamics in stick-slip friction.