Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Optimal Design Method of the Cooling Channel for Manufacturing the Hot Stamped Component with Uniform Strength and Application to V-bending Process

균일 강도 핫스템핑 부품의 제조를 위한 냉각채널 최적 설계 및 V-벤딩 공정에의 적용

  • Lim, Woo-Seung (Precision Manufacturing Systems Division, Pusan National Univ.) ;
  • Choi, Hong-Seok (Precision Manufacturing Systems Division, Pusan National Univ.) ;
  • Nam, Ki-Ju (Precision Manufacturing Systems Division, Pusan National Univ.) ;
  • Kim, Byung-Min (School of Mechanical Engineering, Pusan National Univ.)
  • 임우승 (부산대학교 정밀가공시스템) ;
  • 최홍석 (부산대학교 정밀가공시스템) ;
  • 남기주 (부산대학교 정밀가공시스템) ;
  • 김병민 (부산대학교 기계공학부)
  • Received : 2010.09.06
  • Accepted : 2010.10.19
  • Published : 2011.01.01
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Abstract

In recent years, hot-stamped components are more increasingly used in the automotive industry in order to reduce weight and to improve the strength of vehicles. In hot stamping process, blank is hot formed and press hardened in a tool. However, in hot stamping without cooling channel, temperature of the tool increases gradually in mass production thus cannot meet the critical cooling rate to obtain high strength over 1500MPa. Warpage occurs in the hot stamped component due to non-uniform stress state caused by unbalanced cooling. Therefore, tools should be uniformly as well as rapidly cooled down by the coolant which flows through cooling channel. In this paper, optimal design method of cooling channel to obtain uniform and high strength of the component is proposed. Optimized cooling channel is applied to the hot press V-bending process. As a result of measuring strength, hardness and microstructure of the hot formed parts, it is known that the design methodology of cooling channel is effective to the hot stamping process.

Keywords

References

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