Variations in Contact Stress Distribution of Real Rough Surfaces During Running-In

Abstract

A numerical model for the elastic contact of three-dimensional real rough surfaces has been developed and applied to the study of the variations in contact stress distribution in running-in process. The specimens for calculation and experiment are washers with nominally flat grinding surfaces. The stresses of real contact between specimens at each stage of running-in are calculated and the contact stress distributions are given. It is shown that the contact stress distribution is in an exponential form which could be characterized by one dimensionless parameter: λ, the index of contact stress distribution. The proportion of plastic deformation β may be expressed as a function of λ. The results of the present work confirm the reasonableness of the early opinion that the running-in process can be considered as a gradual increase in the elastic component of deformation of the contact area and a decrease in the proportion of plastic deformation.