The Effect of Valley Location in Two-Process Surface Topography Analysis

In this paper the influence of oil pockets location on extraction of surface topography features was taken into account. Plateau-honed cylinder liners with additionally added dimples were taken in consideration. The effect of dimples location on the application of various procedures (cylinder fitting procedure, polynomial approximation) for areal form removal was taken into account. It was noticed that application of 3rd (or greater) degree of the polynomials can caused false estimation of reference plane; extraction of surface topography features by polynomial approximation cannot provide good results when the distance between dimples is too small. For two-process surfaces (plateau-honed cylindrical elements containing wide and deep valleys) the digital filtering was proposed. Application of robust techniques (robust Gaussian regression filter) allowed for areal form removal improvement. However, some of the wide dimples were distorted when the dimple-to-edge distance was too small (smaller than filter bandwidth value).