Research on Elastic–Plastic Contact Behavior of Hemisphere Flattened by a Rigid Flat

Abstract

The contact behavior of a hemisphere pressed by a rigid plane is of great significance to the study of friction, wear, and conduction between two rough surfaces. A flattening contact behavior of an elastic–perfectly plastic hemisphere pressed by a rigid flat is researched by using the finite element method in this paper. This behavior, influenced by different elastic moduli, Poisson’s ratios, and yield strengths, is compared and analyzed in a large range of interference values, which have not been considered by previous models. The boundaries of purely elastic, elastic–plastic, and fully plastic deformation regions are given according to the interference, maximum mean contact pressure, Poisson’s ratio, and elastic modulus to yield strength ratio. Then, a new elastic–plastic constitutive model is proposed to predict the contact area and load in the elastic–plastic range. Compared with previous models and experiments, the rationality of the present model is verified. The study can be applied directly to the contact between a single sphere and a plane. In addition, the sphere contact can also be used to simulate the contact of single asperity on rough surfaces, so the present proposed model can be used to further study the contact characteristics of rough surfaces.

Analysis of Elastic-Plastic Loading and Unloading Contact between Ellipsoid and Rigid Flat

“…The loading-unloading contact behaviour of an elastoplastic ellipsoid pressed by a rigid flat is relevant to various industries, such as electrical conductance between surfaces, friction, and impact mechanics. [1][2][3][4][5] In engineering, all asperities on the machined surface move in the same direction as the tool relative to the workpiece. This treatment determines the profile of asperities with different curvatures in different directions, and the asperities on the mechanical surface are regarded as ellipsoid asperities.…”