Numerical study of normal contact stiffness: Non-Gaussian roughness and elastic–plastic behavior

Abstract

In this paper, we have studied the effect of the degree of asymmetry and peakedness on the performances of a rough contact. A numerical model is proposed to evaluate the real area, the number of contacting asperities and the normal stiffness. The contact between two rough surfaces was modeled as a contact between a rigid flat and an elastic–plastic rough surface taking into account the work hardening and interaction among asperities. The Pearson system of frequency curves was used to generate non-Gaussian random surfaces. Results show that a negative skewness and/or a low kurtosis improve the contact performances by increasing the normal stiffness. This increase is governed by much more asperities into contact and more elastic behavior.