表面润湿性对橡胶滑动接触界面摩擦特性的影响  

Influence of Surface Wettability on the Sliding Frictional Property of NBR Rubber

作　　者：焦云龙[1] 叶家鑫 刘小君[1] 刘焜[1] JIAO Yunlong;YE Jiaxin;LIU Xiaojun;LIU Kun(Institute of Tribology,Hefei University of Technology,Hefei 230009)

机构地区：[1]合肥工业大学摩擦学研究所,合肥230009

出　　处：《机械工程学报》2019年第1期106-111,共6页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51375132;11472096;51505117);安徽省自然科学基金(1608085QE98)资助项目

摘　　要：针对橡胶滑动接触界面,利用自主研制开发的光学原位观测线性往复式摩擦试验机,通过控制蒸馏水与添加剂的配比,对不同润湿性液体润滑条件下的橡胶滑动摩擦过程进行了试验性探究,在此基础之上建立了固-液接触角与橡胶滑动摩擦因数之间的关联性,以期从微观界面润湿的角度解释湿滑条件下橡胶滑动摩擦因数变化的原因。研究表明:当润滑液进入橡胶滑动接触界面时,橡胶的黏滞效应大幅度降低,导致摩擦因数出现断崖式下跌,稳态摩擦因数减小;随着添加剂配比的降低,固-液接触角逐渐增大,润滑液在固体表面上的铺展与润湿性变差,润滑作用减弱,稳态摩擦因数逐渐增大。另外试验结果分析表明,固-液接触角与稳态滑动摩擦因数具有一定的线性相关性(R^2≈0.92),摩擦因数随着接触角的增大而增大。Based on the independently developed optical in situ linear reciprocation tribotester,sliding tests of NBR rubber are performed under different lubrication conditions.The lubricants have different wettability which is controlled by the additive ratio.The higher additive ratio means the lubricants with better spreading and wetting behavior on the solid substrates.A new theoretical model of rubber sliding friction is constructed under wet conditions,and we try to explain the decrease of sliding friction coefficient during the transition process(the contact interface changes from dry to wet)from interface wettability perspective.In addition,the influence of surface wettability on the friction property is studied and the relationship between the contact angle and friction coefficient is constructed.Results show that the viscosity effect of rubber sharply decreases when the lubricant flows into the contact interface in a short time;with the decrease of additive ratio,the contact angle of lubricant on the solid surface gradually decreases and the static friction coefficient increases.It is concluded that the contact angle of lubricant is linear with static friction coefficient(R^2≈0.92),the experimental results have a great coherence with the theoretical model.

关 键 词：橡胶摩擦 接触界面 表面润湿性 黏滞效应 

分 类 号：TH117[机械工程—机械设计及理论]