Evolution of real area of contact due to combined normal load and sub-surface straining in sheet metal  

作　　者：Meghshyam SHISODE Javad HAZRAT Tanmaya MISHRA Matthijn DE ROOIJ Ton VAN DEN BOOGAAED 

机构地区：[1]Nonlinear Solid Mechanics,Faculty of Engineering Technology,University of Twente,Enschede 7522 NB,The Netherlands [2]Surface Technology and Tribology,Faculty of Engineering Technology,University of Twente,Enschede 7522 NB,The Netherlands

出　　处：《Friction》2021年第4期840-855,共16页摩擦（英文版）

摘　　要：Understanding asperity flattening is vital for a reliable macro-scale modeling of friction and wear.In sheet metal forming processes,sheet surface asperities are deformed due to contact forces between the tools and the workpiece.In addition,as the sheet metal is strained while retaining the normal load,the asperity deformation increases significantly.Deformation of the asperities determines the real area of contact which influences the friction and wear at the tool-sheet metal contact.The real area of contact between two contacting rough surfaces depends on type of loading,material behavior,and topography of the contacting surfaces.In this study,an experimental setup is developed to investigate the effect of a combined normal load and sub-surface strain on real area of contact.Uncoated and zinc coated steel sheets(GI)with different coating thicknesses,surface topographies,and substrate materials are used in the experimental study.Finite element(FE)analyses are performed on measured surface profiles to further analyze the behavior observed in the experiments and to understand the effect of surface topography,and coating thickness on the evolution of the real area of contact.Finally,an analytical model is presented to determine the real area contact under combined normal load and sub-surface strain.The results show that accounting for combined normal load and sub-surface straining effects is necessary for accurate predictions of the real area of contact.

关 键 词：asperity flattening real area of contact sub-surface strain zinc coating sheet metal forming 

分 类 号：TG14[一般工业技术—材料科学与工程]