Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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A Study on Laser Weldability of Al-Si Coated 22MnB5 Steel for TWB Hot Stamping

Al-Si 도금된 22MnB5강의 핫스탬핑 TWB 적용을 위한 레이저용접성 고찰

  • Kim, Yong (Center for Robot & Manufacturing, Institute for Advanced Eng.) ;
  • Park, Ki-Young (Center for Robot & Manufacturing, Institute for Advanced Eng.) ;
  • Lee, Bo-Young (Dept. of Aerospace and Mechanical Eng. Korea Aerospace Univ.)
  • 김용 (고등기술연구원 로봇/생산기술센터) ;
  • 박기영 (고등기술연구원 로봇/생산기술센터) ;
  • 이보영 (한국항공대학교 항공우주기계공학부)
  • Received : 2012.11.27
  • Accepted : 2013.04.22
  • Published : 2013.04.30
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Abstract

Recently the use of ultra high strength steels(UHSS) in structural and safety component is rapidly increasing in the automotive industry. Furthermore, it commonly use in tailor welded blank laser welding process before hot stamping to reduce lightweight vehicle. However TWB process is to be a problem about welded strength after hot stamping because it's welded before heat treatment. Therefore, in this study, laser welds of TWB after heat treatment were analyzed for changes in the characteristics, especially the impact on the oxidation and decarburization in order to prevent pre-coated Al-Si layer welds on the properties for intensive investigation. As a result, the degradation of the TWB weldments changes in the heat treatment conditions alone, without any pre-treatment of the coating layer has confirmed that there is a limitation on the improvement. Furthermore Al-Si elements are overall distributed on the weldment and it specially concentrated along the fusion line. Hardness value of Al-Si segregation area is less than 350Hv and tensile strength showed just 78~83% compared with substrate. Accordingly, we proved that both side Al-Si coating should be removed in order to ensure the strength of the substrate.

Keywords

References

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  1. Effect of Coating Thickness on Microstructures and Tensile Properties in Yb:YAG Disk Laser Welds of Al-Si Coated Boron Steel vol.31, pp.3, 2013, https://doi.org/10.5781/KWJS.2013.31.3.66
  2. Effect of keyhole mode on weld shape and mechanical properties of thin sheets of Al-Si coated 22MnB5 steel vol.30, pp.4, 2018, https://doi.org/10.2351/1.5052155