{"title":"Computation and Validation of the Stress Distribution around a Circular Hole in a Slab Undergoing Plastic Deformation","authors":"S. D. El Wakil, J. Rice","country":null,"institution":"","volume":105,"journal":"International Journal of Mechanical and Mechatronics Engineering","pagesStart":1634,"pagesEnd":1638,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10002317","abstract":"The aim of the current work was to employ the finite\r\nelement method to model a slab, with a small hole across its width,\r\nundergoing plastic plane strain deformation. The computational\r\nmodel had, however, to be validated by comparing its results with\r\nthose obtained experimentally. Since they were in good agreement,\r\nthe finite element method can therefore be considered a reliable tool\r\nthat can help gain better understanding of the mechanism of ductile\r\nfailure in structural members having stress raisers. The finite element\r\nsoftware used was ANSYS, and the PLANE183 element was utilized.\r\nIt is a higher order 2-D, 8-node or 6-node element with quadratic\r\ndisplacement behavior. A bilinear stress-strain relationship was used\r\nto define the material properties, with constants similar to those of the\r\nmaterial used in the experimental study. The model was run for\r\nseveral tensile loads in order to observe the progression of the plastic\r\ndeformation region, and the stress concentration factor was\r\ndetermined in each case. The experimental study involved employing the visioplasticity\r\ntechnique, where a circular mesh (each circle was 0.5 mm in\r\ndiameter, with 0.05 mm line thickness) was initially printed on the\r\nside of an aluminum slab having a small hole across its width.\r\nTensile loading was then applied to produce a small increment of\r\nplastic deformation. Circles in the plastic region became ellipses,\r\nwhere the directions of the principal strains and stresses coincided\r\nwith the major and minor axes of the ellipses. Next, we were able to\r\ndetermine the directions of the maximum and minimum shear\r\nstresses at the center of each ellipse, and the slip-line field was then\r\nconstructed. We were then able to determine the stress at any point in\r\nthe plastic deformation zone, and hence the stress concentration\r\nfactor. The experimental results were found to be in good agreement\r\nwith the analytical ones.","references":null,"publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 105, 2015"}