Contact mechanics of fractal surfaces by spline assisted discretisation

TL;DR

This paper introduces a spline-assisted discretization method to analyze contact mechanics of fractal surfaces, revealing how surface fractality influences contact stiffness and area evolution under load.

Contribution

The paper presents a novel spline-assisted discretization approach for modeling contact mechanics of fractal surfaces, capturing the effects of surface fractality on contact behavior.

Findings

Higher fractality leads to lower initial contact stiffness.

Linear increase of true contact area with load is observed.

Method aligns with existing numerical and experimental results.

Abstract

We present a newly developed approach for the calculation of interfacial stiffness and contact area evolution between two rough bodies exhibiting self affine surface structures. Using spline assisted discretization to define localised contact normals and surface curvatures we interpret the mechanics of simulated non-adhesive elastic surface-profiles subjected to normal loading by examining discrete contact points as projected Hertzian spheres. The analysis of rough-to-rough contact mechanics for surface profiles exhibiting fractal structures, with fractal dimensions in the regime 1 2, reveals the significant effect of surface fractality on contact mechanics and compliance with surfaces having the same mean roughness but higher fractality showing lower contact stiffness in conditions of initial contact for a given load. The predicted linear development of true contact area with load was found to be consistent with diverse existing numerical and experimental studies. Results from this model demonstrate the applicability of the developed method for the meaningful contact analysis of hierarchical structures with implications for modelling tribological interactions between pairs of rough surfaces