Effect of Skewness and Roughness Level on the Mechanical Behavior of a Rough Contact

Abstract

Abstract. In this work, we investigate the effects of roughness level and asymmetry of profile on the mechanical behavior of an engineering surface. A numerical model was performed to simulate bi-dimensional surfaces with different roughness parameters (The arithmetic average height parameter R a and skewness) values. This model predicts the contact load, real area and interfacial stiffness. It takes into account the elastic-plastic material behavior, asperities interactions and more realistic geometry than the analytical models. Both symmetric and asymmetric profiles were simulated. Symmetric (Gaussian) profiles were generated through experimentally measured surfaces. These profiles were artificially edited in order to put forward the effect of roughness parameters on the contact performances. The Pearson system of frequency curves is used to produce asymmetric profiles with the same roughness level. The effect of crushing and roughness level as well as the skewness parameter on the contact performance in terms of real area, contact load and interfacial stiffness was analyzed.

Change in Dimensions and Surface Roughness of 42CrMo4 Steel after Nitridation in Plasma and Gas

“…Upon closer examination of the obtained profiles and the use of multiparameter evaluation with parameters Rz, Rsk and Rku, it was found that nitriding processes lead to changes in the surface roughness, which are directly related to the functional behavior of the components. The appropriateness of using the Rsk and Rku parameters in the evaluation of functional surfaces is stated, for example, in [66,67]. In the case of the Rz parameter, changes were found in the form of decreases in values after the nitriding processes, from which it can be concluded that the heights of the peaks and the depths of the valleys of the nitrided surfaces are reduced.…”

Surface roughness assessment on hole drilled through the identification and clustering of relevant external and internal signal statistical features

“…Wern et al [17] show that this process generates a negative skewness and a high kurtosis in the case of drilling processes. Amor et al [19] showed that profiles with the same level of roughness Ra and different degree of skewness -Rsk-do not have the same contact properties. They also showed that the negative skewness and the lower value of Ra are advisable to achieve a high normal contact stiffness.…”