Couple-Stress Effects on Stress Concentration Around a Cylindrical Inclusion in a Field of Uniaxial Tension

Abstract

This investigation is concerned with the effects of couple stresses on the elastic behavior of a composite body, formed by the presence of a cylindrical inclusion within an infinite exterior region. The exterior region is assumed to be subjected to uniaxial tension at infinity. The inclusion and the exterior are assumed to have different elastic constants G1, ν1 and G2, ν2 respectively, as well as distinct characteristic lengths l1 and l2. These characteristic lengths provide a measure of the granular or crystalline substructure of the materials and introduce the effect of couple stress. Particular attention is focused on the stress-concentration factor at the interface between the inclusion and the exterior region. The results are evaluated for various ratios of G1:G2 and l1:l2. They are shown to depend on those ratios as well as on the dimensions of the inclusion.