The main step in a contact analysis between rough surfaces is the evaluation of the pressure distribution developed on the real contact area. The normal pressure distribution can be used further to predict subsurface stress, interfacial friction and surface wear. Only few real rough surfaces are Gaussian, most of that produced by manufacturing processes are non-Gaussian having an arbitrarily orientation. The definition of the roughness will include, in addition to the spatial characteristics, information about spectral characteristics of the surface, described with the use of autocorrelation function ACF.
Conjugate Gradient Method in conjunction with Discrete Convolution Fast Fourier Transform was refined and applied to solve the constrained system of equations that governs the pressure distribution between rough surfaces subjected to contact loading in elastic dry conditions. The paper reveals the role played by the spatial characteristics (standard deviation σ, skewness Sk, and kurtosis K) as well as by autocorrelation function on both the non-Hertzian pressure distribution on contact area and depth distribution of von Mises equivalent stress.