Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Design of Punch Shape for Reducing the Punch Wear in the Backward Extrusion

후방 압출 펀치의 마멸 저감을 위한 펀치 형상 설계

  • 김동환 (진주국제대학교 자동차공학과) ;
  • 이정민 (부산대학교 정밀기계공학과 대학원) ;
  • 김병민 (부산대학교 기계공학부)
  • Published : 2004.10.01
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Abstract

Die design to minimize the die wear in the cold forging process is very important as it reduce the production cost and the increase of the production rate. The quantitative estimation fur the die wear is too hard because the die wear is caused by many process variables. So, in this paper, the optimal shape of the backward extrusion punch is newly designed through the FE-analysis considering the surface expansion and Archard wear model in order to reduce the rapid wear rate that is generated for the backward extruded products exceeding the forming limit. The main shape variables of the backward extrusion punch are the flat diameter, angle, and round of the punch nose part. As the flat diameter and angle of the punch nose are larger, the surface expansion is reduced and the wear rate is decreased according to the reduction of the punch round. These results obtained through this study can be applied to the real manufacturing process.

Keywords

References

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