Non-Linear Increase of the Real Contact Area of PMMA Blocks and the Related Contact Model

作     者：Zhijun Luo Kai Wu Shaoze Yan Zhijun Luo;Kai Wu;Shaoze Yan

作者机构：Key Laboratory of Tribology in Advanced EquipmentSchool of Mechanical EngineeringTsinghua UniversityBeijing 100084China PhD Innovation Workstation of Unit 96963 of Rocket Application CenterBeijing 100085China China Academy of Launch Vehicle TechnologyBeijing 100076China 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报(英文版))

年 卷 期：2025年第38卷第1期

页      面：261-272页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：Supported by National Natural Science Foundation of China(Grant No.11872033) Beijing Municipal Natural Science Foundation(Grant No.3172017) 

主　　题：Real contact area GW model MB model Total reflection Non-linear increase 

摘      要：Many experiments have supported the contact models,such as the GW and MB models,but the majority of previous validations have been performed under light loads,resulting in a linear relationship between normal force and contact ***,the real contact area fraction should never equal one;there must be a limit smaller than the apparent area,implying that the real contact area cannot increase linearly *** this paper,the real contact area between two polymethylmethacrylate(PMMA)blocks under heavy load is measured using the total reflection method,and the contact area is analyzed using the image processing *** results show that the real contact area increases with normal load linearly in light loads but non-linearly in heavy loads;the number of contact spots increases with load linearly in light loads but also non-linearly in heavy loads,synchronous with the change in the real contact *** GW,MB,and Zhao,Maietta,and Chang(ZMC)models were used to predict the experiment results,but none of them predicted the non-linear stage.A revised GW model based on the bulk deformation hypothesis performs better in predicting the non-linear *** study’s findings can be applied to PMMA or other similar materials,and they can serve as a useful reference for future research on the contact mechanisms of other materials.