The effect of plasticity on the stress-distribution of thin notched plates in tension

Abstract

An explicit solution of the stress-distribution in notched plates under conditions of plane-stress is given in the elasto-plastic domain of straining. The material is considered as elastic-perfectly plastic and isotropic obeying the Mises yield condition and the Prandtl-Reuss incremental stress-strain relations. Elastic and plastic components of strains are determined by using information from birefringent coatings cemented on the surface of the specimens and observed in normal circularly or linearly polarized light. These measurements are complemented with data from an electrical analogy which yield the ϵ x -strain distribution. Thin fat plates containing either symmetrical semi-circular grooves or deep notches of various flank angles are subjected to a uniform tension. Four cases of flank angles are considered lying between 0 and 120 deg. The minimum width of all plates is taken constant and equal to the half of the width of the plates. The analysis of the state of stress is restricted to the initial part of the loading path from an incipient plastic deformation up to an impending plastic flow. The variation of stress distribution with the evolution of plastic enclaves is studied and the influence of the severity of notches on the mode of spreading of plastic zones is determined.