Modeling Solid Contact between Rough Surfaces with Various Roughness Parameters

A solid contact model with high accuracy is required for mixed lubrication calculation to predict friction loss and wear in sliding parts by computer-aided engineering; however, existing models have numerous limitations. A new asperity contact model was constructed to determine contact states using the roughness parameters of pairs of surfaces. Although the contact states differed greatly depending on differences in skewness and kurtosis, the calculated results of the proposed model agreed well with the results of direct calculation between various pairs of surfaces. Furthermore, even when the pairs of rough surfaces had the same composite roughness, skewness, and kurtosis, the trend of the increase in the contact force was different when the individual skewness and kurtosis of the surfaces were different. Therefore, we determined that it is necessary to carry out detailed asperity contact calculations when the two rough surfaces differ greatly. We plan to further investigate the influence of skewness and kurtosis on the contact tendency for the elastoplastic deformation by the extended model considering the contact stress distribution of asperities.