弹塑性接触粗糙表面切向载荷-位移模型
Tangential Load-Displacement Model of Elastic-Plastic Rough Contact Surfaces

针对在法向载荷和切向载荷联合作用下粗糙表面的接触问题,建立了一种同时考虑微凸体弹性接触和塑性接触的接触界面切向载荷-位移新模型。对弹性接触的微凸体,采用Hertz弹性理论描述法向接触载荷-变形关系,采用Mindlin微观滑移理论解描述切向载荷-位移关系;对塑性接触的微凸体,采用Abbott和Firestone塑性接触理论描述法向接触载荷-变形关系,在切向采用Fujimoto模型的切向载荷-位移关系。利用概率统计分析方法,建立了整个粗糙表面切向载荷-位移关系。将模型与仅考虑微凸体弹性接触情况的模型进行了对比,研究了不同模型参数对切向载荷-位移关系的影响。结果表明:考虑微凸体弹塑性接触的模型能够更好地描述粗糙表面切向载荷-位移关系;微凸体高度分布密度函数的方差增大,相同平均接触距离下,切向载荷？参灰乒叵凳芩苄越哟ノ⑼固宓挠跋煸龃？;方差相同时,平均接触距离增大,切向载荷？参灰乒叵档男甭试龃蟆？
A tangential load？？displacement model between rough contact surfaces is developed in this paper. Elastically and plastically deformed asperities are considered simultaneously. For the elastically deformed asperities, the classic Hertz elastic contact solution and Mindlin micro？？slip model are used to model the load？？displacement relationship. For the plastically deformed asperities, the fully plastic contact theory of Abbott and Firestone, and the Fujimoto tangential contact model are implemented. The tangential load？？displacement relationship between rough surfaces is formulated by GW probability statistics approach. The proposed model is compared with the model where only elastically deformed asperities are considered. The effects of model parameters on the tangential load？？displacement behaviors are investigated. The results show that the proposed model can describe the nonlinear behavior of the tangential load？？displacement relationship between rough surfaces more rationally. With the increase of roughness, the tangential load？？displacement relationship is controlled by plastic contact asperities. The slope of the tangential load？？displacement curve increases with the average contact distance when the roughness parameter holds constant