依据修正GW理论的结合部法向接触研究  

Normal contact of joint interface using revised GW theory

作　　者：田红亮[1] 方子帆[1] 赵春华[1] 朱大林[1] 

机构地区：[1]三峡大学机械与动力学院,湖北宜昌443002

出　　处：《华中科技大学学报（自然科学版）》2014年第6期38-42,47,共6页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51275273);三峡大学博士科研启动基金资助项目(KJ2012B013)

摘　　要：考虑两半球体单峰塑性接触时球台体积守恒建立实际接触面积、法向接触载荷、塑性指数的解析解,通过中间自变量———两接触粗糙表面的间距,建立了机械结合部法向接触的力学模型.计算与分析结果表明:在给定法向总接触载荷下,两接触粗糙表面的间距随塑性指数的增加而增加;对于非常光滑表面或硬材料,接触几乎始终为弹性;表面越粗糙或材料越柔软,更多塑性接触会出现,未计及塑性接触的GW理论低估两接触粗糙表面的间距;在给定法向总接触载荷下,总接触面积随塑性指数的增加而减小;在非常高塑性指数下,弹性接触所占比例极少;在较低塑性指数下,塑性接触面积对总实际接触面积的贡献非常小;修正GW弹塑性接触理论适用于法向接触载荷极大的情况.The analytical solutions for the true contact area,normal contact load and plasticity index were constructed considering spherical platform volume conservation when two hemispherical asperities plastically contacted.In terms of the medial independent variable named separation between two contacting rough surfaces,the mechanics model of machined joint interface were established.The calculation and analysis show that under a given normal total contact load,the separation between two contacting rough surfaces will increase with the plasticity index.For very smooth surfaces or hard materials,the contact is mostly elastic throughout.As the surface becomes rougher or the material becomes softer,therefore more plastic contacts occur,and the GW（Greenwood-Williamson）theory not calculating plastic contact underestimates the separation between two contacting rough surfaces.The total contact area,under a given normal total contact load,diminishes with the increasing of plasticity index.At very high values of the plasticity index,the proportionality of elastic contact is very small. At low plasticity indexes,the contribution of plastic contact area to the total true contact area is very moderate.The revised GW elastic-plastic contact theory is applicable under the instance of large normal contact load.

关 键 词：弹塑性接触理论 塑性指数 法向总接触载荷 修正GW理论 总接触面积 两表面间距 

分 类 号：TH113.1[机械工程—机械设计及理论]