Effects of vibratory finishing of 304 stainless steel samples on areal roughness parameters: A correlational analysis for anisotropy parameters

Abstract

Characterizing abrasive manufacturing processes and their resulting surfaces has been subject to numerous examinations. Because ground surfaces are inherently stochastic, surface anisotropy is a particular interesting feature as it describes the general effectiveness of the finishing process that should remove deterministic patterns from the surface topography. In the standardization process of areal surface topography measurement, different approaches for quantifying topography randomness have been proposed. This paper describes a comprehensive analysis of the resulting surface anisotropy of a vibratory finishing process. Experiments are carried out by measuring the same surface area spot after various lengths of time of vibratory finishing. After a rough grind, a vibratory finishing process is applied to multiple samples and after different time steps in the finishing process, the surface topography is measured. The topography datasets are evaluated in order to determine the progression of the loss of anisotropy due to the stochastic finishing process. Several techniques to characterize the anisotropy of a surface are applied and compared. A correlational analysis to other areal surface texture parameters was performed, finding that texture aspect ratio (Str) was the best descriptor for directionality because it had little correlation to other parameters. The parameter had less than 40% correlation to all other examined parameters – indicating that other effects like the change in the roughness amplitude do not falsify the correct determination of the anisotropy when the parameter is applied.