Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Effects of Electrode Shape on Electrode Life of Resistance Spot Welding of Mg Alloy

Mg 합금 저항 점 용접의 연속 타점 수명에 미치는 전극 형상의 영향

  • Choi, Dongsoon (Advanced Welding & Joining Group, Korea Institute of Industrial Technology) ;
  • Kang, Moonjin (Advanced Welding & Joining Group, Korea Institute of Industrial Technology) ;
  • Ryu, Jaewook (MKE Metal R&D Support Platform, KOMERA) ;
  • Kim, Dongcheol (Advanced Welding & Joining Group, Korea Institute of Industrial Technology)
  • 최동순 (한국생산기술연구원 용접접합연구그룹) ;
  • 강문진 (한국생산기술연구원 용접접합연구그룹) ;
  • 류재욱 (한국금속재료연구조합 금속재료 R&D 지원단) ;
  • 김동철 (한국생산기술연구원 용접접합연구그룹)
  • Received : 2013.06.18
  • Accepted : 2014.01.10
  • Published : 2014.05.01
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Abstract

According to weight lightning trend of automobile body, necessity of resistance spot welding (RSW) of Mg alloy on automobile industry is increasing rapidly because of the highest specific strength among commercial metals. Mg alloy has low electric resistance and high thermal conductivity like as Al alloy, so that needs applying high current in short time when welding. Thick oxide film of Mg alloy pollutes the electrodes and makes partial current carrying paths when on welding. Partial current carrying paths signify excessive concentration of current. There can initiate expulsion easily and reduces electrode life rapidly. Generating partial current carrying paths and expulsions are influenced by shapes of electrode. Therefore, electrode life also influenced by shape. In this study, we perform life test of RSW electrode of radius type. Measure tensile shear load and nugget size every spot alternately. As a result, radius type electrode can extend life over twice as dome type electrode.

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References

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