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http://dx.doi.org/10.7736/KSPE.2015.32.6.509

Finite Element Analysis for Improvement of Folding Defects in the Forging Process of Subminiature Screws  

Lee, Ji Eun (Department of Mechanical System and Design Engineering, Seoul National University of Science and Technology)
Kim, Jong Bong (Department of Mechanical and Automotive Engineering, Seoul National University of Science and Technology)
Park, Keun (Department of Mechanical System and Design Engineering, Seoul National University of Science and Technology)
Publication Information
Journal of the Korean Society for Precision Engineering / v.32, no.6, 2015 , pp. 509-515 More about this Journal
Abstract
Recent trends to reduce the size of mobile electronics products have driven miniaturization of various components, including screw parts for assembling components. Considering that the size reduction of screws may degenerate their joining capabilities, the size reduction should not be limited to the thread region but should be extended to its head region. The screw head is usually manufactured by forging in which a profiled punch presses a billet so that plastic deformation occurs to form the desired shape. In this study, finite element (FE) analysis was performed to simulate the forging process of a subminiature screw; a screw head of 1.7 mm diameter is formed out of a 0.82 mm diameter billet. The FE analysis result indicates that this severe forging condition leads to a generation of folding defects. FE analyses were further performed to find appropriate punch design parameters that minimize the amount of folding defects.
Keywords
Finite element analysis; Subminiature screw; Forging; Folding;
Citations & Related Records
Times Cited By KSCI : 7  (Citation Analysis)
연도 인용수 순위
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