Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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Hardness Estimation of Laser Welded Boron Steel Welds with the Carbon Equivalent

탄소 당량식을 이용한 고강도 보론강의 레이저 용접부 경도 예측

  • 전인환 (한국생산기술연구원 용접.접합그룹) ;
  • 김철희 (한국생산기술연구원 용접.접합그룹) ;
  • 김재도 (인하대학교 기계공학과 대학원)
  • Received : 2016.06.23
  • Accepted : 2016.08.16
  • Published : 2016.10.31
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Abstract

The hardness of laser weldments has been predicted by using several carbon equivalent equations and estimation models. In this study, authors extended the model to boron steel sheets which are adopted for the hot press forming process. four kinds of boron steels with the strengths from 1500 MPa to 1900 MPa were considered and the hardness profiles of weldments was measured from the experiments of this study and the references. The traditional "Kaizu" equation could predict the hardness with an accuracy of -4.9% error although the Kaizu equation does not consider the boron content. Modified carbon equivalents were suggested by adding a term as like 5B or 14B into the Kaizu equation, and it could improve the accuracy of the prediction model.

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References

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