Finite element modeling of the elastic-plastic contact between two rough surfaces

In order to investigate the complex contact behaviors of micro-rough interfaces, this paper proposed a novel finite element method (FEM) for simulating the contact between two rough surfaces. The numerical methods for generating Gaussian and non-Gaussian rough surfaces were introduced, and the contact surfaces were produced with given autocorrelation function (ACF) and the first four moments of surface height. Finite element (FE) models were constructed based on the generated rough surfaces, in which 3D structural modeling and meshing strategies were utilized to improve the mesh quality and solution efficiency. A 3D finite element analysis (FEA) was conducted to investigate the contact characteristics including the contact stiffness, real contact area and the contact pressure distribution of rough interfaces. The results of the contacts between two rough surfaces were compared with those of the conventional equivalent contact models in which an equivalent rough surface contacted with a rigid smooth plane. The proposed FEM makes it effective to predicate or evaluate the contact characteristics of the contact of two rough surfaces, and may provide a new way to optimize the design of surface topographies and improve the performances of contact interfaces.