Characterization of elastic-plastic corner deformation and stress fields

Abstract

Purpose The purpose of this paper is to present the characteristics of elastic-plastic deformation and stress fields at the intersection of a crack front and the free surface of a three-dimensional body, referred to as corner fields. Design/methodology/approach The structures of elastic-plastic corner deformation field were assessed experimentally by looking at the corner border displacement and strain fields on the surface of a compact tension (CT) specimen using digital image correlation method. For assessment and verification purposes, the results were compared with the fields predicted through finite element analysis. The latter method was used further to assess the corner stress field. Findings The characteristics of displacement, strain and stress fields in the vicinity of a corner vertex in a finite geometry CT specimen in a strain hardening condition are independent of load and geometry. One of the distinctive features that becomes evident in this study is that the stress state at the corner vertex at θ=0° is a simple uniaxial tension. Originality/value This paper provides some insights on the structure of elastic-plastic corner fields that could optimistically be served as a fundamental framework towards the development of analytical solutions for elastic-plastic corner fields.