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Design of the Stiffened Punch for Stamping of Lead Frame by Buckling Analysis  

Ko, Dae-Cheol (부산대학교 동남권부품소재산학협력혁신연구소)
Lee, In-Soo (부산대학교 대학원 정밀기계공학과)
Ahn, Byung-Hwan ((주)삼우테크)
Kim, Byung-Min (부산대학교 정밀정형 및 금형가공 연구소)
Publication Information
Journal of the Korean Society for Precision Engineering / v.23, no.9, 2006 , pp. 68-75 More about this Journal
Abstract
The lead frame manufactured by stamping process plays an important role in connecting semiconductor to PCB board. As a result of the miniaturization of semiconductor, its corresponding lead frame punch has been narrow. In case of the punch with high slenderness ratio such as lead frame punch, the punch can be broken suddenly due to buckling. To prevent the fracture of lead frame punch, some manufacturers have experientially attached stiffeners to weak parts of punch. The purpose of this study, therefore, is to suggest the guideline far design of stiffened punch. The optimal position and the number of stiffeners to be attached to punch are investigated by elastic buckling analysis. The elastic buckling analysis consists of the eigenvalue buckling analysis and nonlinear buckling analysis. The critical buckling load of elastic buckling analysis is compared with that of buckling test. Finally, the guideline far attaching stiffeners is suggested through analysis of cross section of lead frame punch such as moment of inertia and eccentricity.
Keywords
Lead Frame; Inner Lead Pitch(ILP); Elastic Buckling Analysis; Critical Buckling Load; Stiffener;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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