Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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A Study on Spot-Welding Characteristics and Material Analysis of Boron Steel for Hot-Stamping under Different Heat-Treatment Conditions

핫스탬핑용 보론 강판의 열처리 조건에 따른 재질분석 및 점용접 특성 연구

  • Je, Hwan-Il (Dept. of Materials Science and Engineering, Graduate School, Pukyong Nat'l Univ.) ;
  • Son, Chang-Suk (Defence Agency for Technology and Quality) ;
  • Nam, Ki-Woo (Dept. of Materials Science and Engineering, Pukyong Nat'l Univ.)
  • 제환일 (부경대학교 대학원 재료공학과) ;
  • 손창석 (국방기술품질원) ;
  • 남기우 (부경대학교 재료공학과)
  • Received : 2010.07.19
  • Accepted : 2011.01.21
  • Published : 2011.04.01
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Abstract

The hot-stamping technique is used to manufacture high-strength parts by press forming by heating at a temperature above the Austenite transformation temperature and then rapid cooling. Boron steel, which contains a very small amount of boron, is one of the materials used for hot stamping. The purpose of this study is to show the microstructures and to investigate the mechanical properties under different heat-treatment conditions. The heat treatment of water quenching was conducted at the various temperatures and different elapsed times. These can be practical data useful when boron steels are used for hot stamping. Furthermore, the microstructures and mechanical properties of the spot-welded specimen with coatings and counterpart materials (SPRC 340, SPRC 590) is investigated in order to determine the welding characteristics of boron steel at different welding condition.

최근 차체 경량화를 위한 여러 가지 방법 가운데 고온에서 가공하여 성형성을 확보하고, 이후 열처리를 통하여 고강도를 가질 수 있는 프레스 열간 성형 및 핫스탬핑 기술이 각광을 받고 있으며, 이에 따라 핫스탬핑용 재료인 보론 첨가 강판의 수요도 늘어나고 있는 추세이다. 본 연구에서는 핫스탬핑용보론 첨가 강판의 우수한 경화능을 보이는 임계 최적 열처리 조건을 파악하고자, Al+Si 코팅이 된 보론강판을 각기 다른 온도로 열처리하여 수냉 조건에 따른 기계적 특성 및 조직을 관찰하였다. 또한, 이 결과를 토대로 선별된 기계적 특성이 우수한 보론강 시험편과 일반 냉연 강판인 SPRC 340과 SPRC 590 2종류의 상대재를 활용하여 특정 점용접 조건에서 용접을 실시하고, 보론강 및 상대재의 기계적 특성 변화에 따른 용접 후의 기계적 특성 및 조직, 그리고 코팅층 유무에 따른 특성 변화를 연구하였다.

Keywords

References

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  2. A study on mechanical properties of laser-welded blank of a boron sheet steel by laser ablation variable of Al-Si coating layer vol.14, pp.2, 2013, https://doi.org/10.1007/s12541-013-0039-5
  3. The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (I) - Laser Weldability of Al-Si Coated Boron Steel Used for Hot Stamping Process - vol.38, pp.12, 2014, https://doi.org/10.3795/KSME-A.2014.38.12.1367
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