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http://dx.doi.org/10.3795/KSME-A.2013.37.7.841

Enhancement of Dimple Formability in Sheet Metals by 2-Step Forming  

Kim, Hasung (Dept. of Mechanical Engineering, Sogang Univ.)
Kim, Minsoo (Dept. of Mechanical Engineering, Sogang Univ.)
Lee, Hyungyil (Dept. of Mechanical Engineering, Sogang Univ.)
Kim, Naksoo (Dept. of Mechanical Engineering, Sogang Univ.)
Kim, Dongchoul (Dept. of Mechanical Engineering, Sogang Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers A / v.37, no.7, 2013 , pp. 841-849 More about this Journal
Abstract
In this study, a 2-step stamping model with an additional 1st stamping tool is proposed to reduce stamping flaws in the curved parts of a dimple in a nuclear fuel spacer grid. First, the strains of curved part of dimple are characterized via a comparison with strain solutions in pure bending. A reference 2D finite element (FE) model of 1-step stamping is then established, and the corresponding maximum strain is obtained. By varying the values of design variables of the 1st stamping tool in the 2-step stamping model, FE solutions are obtained to express the strain as a function of process variables, which provides the optimum values of process variables. Finally, applying these optimum values to a 3D FE model, we demonstrate the enhanced formability of the proposed 2-step stamping model.
Keywords
Forming Process Design; 2-Step Forming; Finite Element Analysis; Response Surface Method; Formability; Forming Limit Diagram;
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Times Cited By KSCI : 1  (Citation Analysis)
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