Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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A Local Softening Method for Reducing Die Load and Increasing Service Life in Trimming of Hot Stamped Part

핫스템핑 부품의 전단가공에서 전단 하중의 감소 및 트리밍 금형 수명 향상을 위한 국부 연화 방법

  • 최홍석 (부산대학교 정밀가공시스템) ;
  • 임우승 (부산대학교 정밀가공시스템) ;
  • 강충길 (부산대학교 기계공학부) ;
  • 김병민 (부산대학교 기계공학부)
  • Received : 2011.07.11
  • Accepted : 2011.09.06
  • Published : 2011.10.01
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Abstract

In general, hot stamped component is trimmed by costly and time consuming laser cutting when the material strength is over 1,500MPa. The aim of this work was to demonstrate that the trimming die life is improved and the trimming load is decreased by lowering the strength of the region to be trimmed. The model employed in this study was a hat shape, similar to the cross section of many hot stamped products. FE-analysis of hot stamping process was performed to evaluate the effect of tool shape on cooling rate at the area to be trimmed. The best tool shape was thus identified, which created slower cooling and lower hardness at the region to be trimmed. The wear at the cutting tool edge was also reduced.

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References

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