Analytical Expression for the Atomic Friction of a Single Asperity Based on the Prandtl-Tomlinson Model  

作　　者：Weike Yuan Yue Ding Gangfeng Wang Xinrui Niu 

机构地区：[1]Department of Engineering Mechanics,SVL,MML,Xi’an Jiaotong University,Xi’an,710049,China [2]Department of Mechanical Engineering,City University of Hong Kong,Hong Kong SAR,999077,China

出　　处：《Acta Mechanica Solida Sinica》2024年第3期416-422,共7页固体力学学报（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.12302141,12372100,and 12102322);the China Postdoctoral Science Foundation(Grant No.2023M732799);the General Research Fund(Project No.CityU 11302920)from the Research Grants Council of the Hong Kong Special Administrative Region is acknowledged.

摘　　要：The Prandtl-Tomlinson(PT)model has been widely applied to interpret the atomic friction mechanism of a single asperity.In this study,we present an approximate explicit expression for the friction force in the one-dimensional PT model under quasi-static conditions.The‘stick-slip’friction curves are first approximated properly by sawtooth-like lines,where the critical points before and after the‘slip’motion are described analytically in terms of a dimensionless parameterη.Following this,the average friction force is expressed in a closed form that remains continuous and valid forη>1.Finally,an analytical expression for the load dependence of atomic friction of a single asperity is derived by connecting the parameterηwith the normal load.With the parameters reported in experiments,our prediction shows good agreement with relevant experimental results.

关 键 词：Atomic friction Stick-slip friction Prandtl-Tomlinson model Friction force microscope 

分 类 号：O34[理学—固体力学]