On the Role of Roughness in the Indentation of Viscoelastic Solids

Abstract

AbstractA numerical boundary element methodology is employed to understand how fractality intervenes when a 1D rigid rough profile indents a linear viscoelastic half-plane. The focus is, in particular, on the viscoelastic dissipation and how this is influenced by the profile statistical parameters, namely, the mean square roughness $$h_{\rm rms}$$ h rms of the profile, the mean square slope $$m_{2}$$ m 2 and the Hurst exponent H. Our numerical investigation, properly supported by a dimensional analysis, reveals that, in the one-dimensional case under investigation, the leading role is played by $$h_{\rm rms}$$ h rms and, thus, mainly by the large scales of the rough spectrum. Clearly, on an experimental level, this implies that a simple measure of the roughness parameter $$h_{\rm rms}$$ h rms is sufficient to determine the viscoelastic dissipation.