Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Study on the Characteristics for the Blanking of Lead Frame with the Rectangular Shape Blanking

사각형 블랭킹을 통한 리드프레임의 블랭킹 특성에 관한 기초연구

  • 임상헌 (영남이공대학 금속금형설계과) ;
  • 서의권 (영남대학교 공업기술연구소) ;
  • 심현보 (영남대학교 기계공학부)
  • Published : 2001.03.01
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Abstract

An experiment is carried out to investigate the characteristics of blanking for copper alloy C194 (t=0.254mm), a kind of IC lead frame material. By varying clearance between die and punch, the shapes of shear profile are examined. Finite element analysis with element deletion algorithm for ductile fracture mode is also carried out to study the effect of clearance theoretically and to compare with experimental results. The rectangular shape specimen with four different corner radius is used to study the characteristics of blanking for straight side and corner region simultaneously. As the result, the ratios measured from the experiment of roll over, burnish, and fracture zone based on intial blank thickness are compared with those of FE analysis. Both experiment and FE analysis show that the amount of roll over and fracture is increased as the clearance increases. It has been found that larger clearance is required than that of straight region when the radius of corner is less than thickness of blank, in order to maintain same quality of shear profile at the corner region.

Keywords

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