Elasto-plastic behaviour of cantilever beams containing varied stress concentration cut out features

Abstract

In machine component design, it is necessary to introduce openings or cut outs to carry out specific service functions such as electrical wiring, piping, and inspection, among others. The introduction of these cut outs results in a high concentration of stress leading to degradation of the component strength, especially under cyclic loading. The geometrical features and orientation of these cut outs relative to the support and the applied loads will also influence the severity of the resulting stress concentration. Of particular interest to this study is the elastic and elasto-plastic behaviour of a cantilever beam containing rectangular, circular or diamond cut outs under plane strain conditions. Four aspects of the work were accordingly examined. The first is concerned with the elasto-plastic load–deflection diagram of the beam containing the cut out features. The second with the finite element predictions of the elastic behaviour and the associated stress concentration factor of the beam in the presence of the cut out features. The third with the elasto-plastic behaviour and etching results showing the remarkable agreement between the two. Finally, in the fourth, we focus our attention to unloading residual stresses. The results offer a complete coverage of the problem and should help in the elasto-plastic design of beams containing stress concentration features.