考虑表面张力的机械结合面特性建模研究  

Modeling of mechanical interface characteristics considering surface tension

作　　者：李玲[1] 王晶晶 云强强 史小辉 蔡安江[1] LI Ling;WANG Jingjing;YUN Qiangqiang;SHI Xiaohui;CAI Anjiang(School of Mechanical and Electrical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学机电工程学院,西安710055

出　　处：《振动与冲击》2020年第17期281-288,295,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金(51305327,51475352);陕西省自然科学基金(2018JM5066)。

摘　　要：表面张力是物质表面层分子间存在的力,它对机械结合面的接触特性有着重要的影响。为此,采用Nayak随机过程模型表征各向同性表面上微凸体的高度与曲率分布,建立考虑表面张力的单个微凸体接触模型,通过高斯-切比雪夫求积公式求解验证了模型的正确性;基于统计学理论将单个微凸体的计算模型扩展到整个粗糙表面上,建立了新的结合面接触模型,揭示了表面张力对结合面接触载荷、真实接触面积以及接触刚度的影响规律。结果表明:当两表面间平均距离相同时,与传统不考虑表面张力的模型相比,新模型具有较大的接触载荷和接触刚度,较小的真实接触面积;当接触载荷增大时,真实接触面积增大的速率随着表面张力的增大而减小;接触刚度随着接触载荷或真实接触面积的增大而增大,且表面张力越大,递增速率越快。Surface tension is a force existing among surface layer molecules of material and significantly affecting contact characteristics of mechanical interface.Here,Nayak random process model was introduced to characterize height and curvature distribution of an asperity on an isotropic surface,and establish a contact model of a single asperity considering surface tension.Gauss-Chebyshev quadrature formula was used to verify the correctness of the model.Then,the calculation model of a single asperity was extended to a whole rough surface based on the statistics theory to build a new contact model of mechanical interface.Effect laws of surface tension on interface contact load,actual contact area,and contact stiffness were revealed.Results showed that when the mean distance between two surfaces keeps the same,compared with the traditional model not considering surface tension,the new model has larger contact load and contact stiffness,and smaller actual contact area;when contact load grows,actual contact area increasing rate drops with increase in surface tension;contact stiffness grows with increase in contact load or actual contact area,the greater the surface tension,the faster the contact stiffness increasing rate.

关 键 词：机械结合面 表面张力 接触特性建模 高斯-切比雪夫求积 

分 类 号：TH113[机械工程—机械设计及理论] O34[理学—固体力学]