一种考虑微凸体法向弹塑性接触的粗糙面力学模型  

A Normal Mechanical Model for Elastic-Plastic Contact of Rough Surface

作　　者：王东[1] 徐超[2] 万强[1] 

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621999 [2]西北工业大学航天学院,西安710072

出　　处：《上海交通大学学报》2016年第8期1264-1269,共6页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金(11372246);中物院科学技术重点基金(2014A0203006);中国工程物理研究创新发展基金(15cxj20)资助

摘　　要：提出一种考虑微凸体弹塑性变形影响的接触载荷、接触面积的粗糙表面法向接触力学模型.将微凸体的接触变形分为3种状态,对完全弹性和完全塑性变形阶段分别采用Hertz弹性接触理论和AF塑性接触模型进行建模,并采用一阶幂指数函数描述混合弹塑性阶段的接触载荷和实际接触面积与接触变形之间的关系,再采用数理统计分析的方法建立了粗糙表面法向弹塑性接触模型.将此模型与完全弹性模型、CEB模型、ZMC模型、KE模型对比,研究了塑性指数对粗糙面接触载荷-平均接触距离的影响.结果表明,该模型能够更好地描述微凸体法向接触载荷与接触变形的变化趋势,模型预测的粗糙表面法向载荷与ZMC和KE模型具有较好的一致性;随着平均接触距离的增加,粗糙面接触载荷逐渐减少;随着塑性指数的增加,不同模型预测的法向接触载荷差异逐渐增大.An elastic-plastic mechanical model was proposed to describe the normal contact load and area of the rough surface.The problem can be considered in three separated contact phases,the ideally elastic phase,the mixed elastic-plastic phase and the fully plastic phase.In the ideally elastic phase,Hertz＇s elastic contact formulations were used;in the fully plastic phase,the classical fully plastic contact modal of Abbott and Firstone was used;and in the mixed elastic-plastic phase,the contact behaviors were approximated by one-order power function interpolation.The contact model of rough surfaces was then formulated by using the probability statistics theory.The proposed model was compared with the ideally elastic model,CEB model,ZMC model,and KE model.The results show that the proposed model can better model the relation between the contact load and deformation of asperity,and the result agrees well with that of the KE model and ZMC model.With the increase of mean separation of rough surfaces,the total contact load decreases.The plasticity index has a great effect on the contact load of different model,and larger plasticity index induces more difference.

关 键 词：弹塑性 一阶幂函数 粗糙表面 概率统计 微凸体 

分 类 号：O343.3[理学—固体力学]