Quality Evaluation of Resistance Spot Welding using Acoustic Emission

음향방출을 이용한 저항 점용접의 용접 품질평가

  • 조대희 (인천대학교 교육대학원 기계교육전공) ;
  • 이장규 (인천대학교 기계공학과) ;
  • 박성완 (인천전문대학 컴퓨터응용기계설계과) ;
  • 조진호 (인천대학교 대학원 기계공학과) ;
  • 김봉각 (충청대학 항공.기계설계학부) ;
  • 우창기 (인천대학교 기계공학과)
  • Published : 2006.08.01

Abstract

In this paper, for the purpose of investigation the acoustic emission(AE) behaviors during resistance spot welding process and tension test of spec steels. As the results present the resistance spot welding method that can get suitable welding qualities or structural integrity estimating method. The resistance spot welding process consists of several stages: set-down of the electrodes; squeeze; current flow; forging; hold time; and lift-off. Various types of AE signals are produced during each of these stages. For tensile-shear test and cross tensile test in resistance spot welded specimens, fracture pa 야 ems are produced: tear fracture; shear fracture; and plug fracture. Tensile-shear specimens strength appeared higher than cross tensile specimens one. In case of tensile-shear specimen happened tear fracture that crack happens in most lower plate. Also, in case of cross tensile specimens, upper plate and lower plate are detached perfect fracture was exposed increases a little as acting force is lower than ordinary welding condition. Therefore, the structure which is combined by resistance spot welding confirmed that welding design must attain so that shear stress may can interact mainly.

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References

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