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arXiv · 2106.16103

Scale-dependent roughness parameters for topography analysis

Antoine Sanner·Wolfram G. Nöhring·Luke A. Thimons·Tevis D. B. Jacobs·Lars Pastewka
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Abstract

The failure of roughness parameters to predict surface properties stems from their inherent scale-dependence; in other words, the measured value depends on the way it was measured. Here we take advantage of this scale-dependence to develop a new framework for characterizing rough surfaces: the Scale-Dependent Roughness Parameters (SDRP) analysis that yields slope, curvature and higher-order derivatives of surface topography at many scales, even on a single topography measurement. We demonstrate the relationship between SDRP and other common statistical methods for analyzing surfaces: the height-difference autocorrelation function (ACF), variable bandwidth methods (VBMs) and the power spectral density (PSD). We use computer-generated and measured topographies to demonstrate the benefits of SDRP analysis, including: novel metrics for characterizing surfaces across scales, and the detection of measurement artifacts. The SDRP is a generalized framework for scale-dependent analysis of surface topography that yields metrics that are intuitively understandable.

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Antoine Sanner, Wolfram G. Nöhring, Luke A. Thimons, Tevis D. B. Jacobs, Lars Pastewka. 2021-06-30. Scale-dependent roughness parameters for topography analysis. https://doi.org/10.1016/j.apsadv.2021.100190

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