Mechanical Properties of Laser-Welded Multi-Material Tailor-Welded Blanks

레이저 TWB된 이종접합강의 기계적 특성

  • Nam, Ki-Woo (Dept. of Materials Science and Engineering, Pukyung Nat'l Univ.) ;
  • Park, Sang-Hyun (Research Institute, Sungwoo Hitech, Co. Ltd.) ;
  • Lee, Kyu-Hyun (Research Institute, Sungwoo Hitech, Co. Ltd.) ;
  • Lee, Mun-Yong (Research Institute, Sungwoo Hitech, Co. Ltd.)
  • 남기우 (부경대학교 재료공학과) ;
  • 박상현 (성우하이텍 기술연구소) ;
  • 이규현 (성우하이텍 기술연구소) ;
  • 이문용 (성우하이텍 기술연구소)
  • Received : 2011.12.12
  • Accepted : 2012.06.18
  • Published : 2012.08.01


In this study, tailor-welded blanks(TWB) were formed between high-strength steel(SABC1470) and cold rolled steels(SPFH590 and SPFC980) to improve passenger safety and reduce the weight of cars. Multi-material TWB specimens were highly strengthened through the heat treatment of SABC1470. The change in tensile strength caused by the stand-by time until water cooling after stamping and the deformation behavior of high-speed bending in a statically indeterminate condition such as in the center-pillar were evaluated. Multi-material TWB specimens that were heat-treated at the same temperature tended to show a decrease in tensile and yield strength, depending on the stand-by time until water cooling. On the other hand, Multi-material TWB specimens(SABC1470+SPFH590) that were heat treated at $850^{\circ}C$ showed good properties that were suitable for ensuring passenger safety in car accidents. From the viewpoint of passenger safety, it is best to use SABC1470 and SPFH590 in the upper and lower area of the center-pillar, respectively.


Center Pillar;Different Material;Tailor Weld Blanks(TWB);Tensile Test;High Speed Bending;Statically Indeterminate


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