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Split Die Design for ECAP with Lower Loads

등통로각압축 공정용 저하중 분리형 금형 설계

  • 진영관 (한국과학기술원 기계공학과) ;
  • 강성훈 (한국기계연구원 소재성형 연구센터) ;
  • 손일헌 (POSCO 선재연구 그룹) ;
  • 임용택 (한국과학기술원 기계공학과)
  • Published : 2008.03.01

Abstract

Equal channel angular pressing (ECAP) is one of the effective methods to produce bulk-nano materials by accumulating plastic strain into the workpiece without changing its cross-sectional shape in the multi-pass processing. However, the forming load becomes higher for manufacturing large specimens using conventional solid or split dies because of friction, flash formation, and usage of dummy specimen. In the present investigation, better split die was designed to reduce the forming loads and improve the geometrical accuracy of the specimen in the multi-pass ECAP. The new die exit channel was also designed to reduce the friction effect. Experiments with AA1050 specimens with a square cross-section were carried out to examine the design goal using the proposed split dies for routes A and C up to four passes. The numerical forming simulations were used to determine the effective geometry of various die models in the present work.

Keywords

Multi-Pass ECAP;Split Die;Forming Load;Deformed Geometry

References

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