Cylindrical indentation in micropolar elasticity

Abstract

Experiments existing in the literature present a scale dependence of the mechanical properties of certain materials. Such scale dependence is observable also in indentation experiments where the attained contact area and average pressure among other experimental outputs show a strong dependence upon the microstructure of the indented material. In this work we will examine the indentation of a rigid cylinder on an elastic half-plane within the context of the micropolar elasticity (also known as Cosserat elasticity). The micropolar theory of elasticity incorporates in addition to the displacement field, an independent kinematical microrotation field. Our results show the dependence of the shape of the pressure distribution, the average pressure and the width of the contact site below the indenter upon the microstructure of the material described through the material length as introduced through the micropolar theory. A comparison of the results with those obtained by the classical theory and the couple stress theory as well as a full field solutions regarding equivalent stresses are presented. © 2021