[論文] 인장-전단하중을 받는 일점 Spot용접재의 파괴역학적 피로강도 평가

다국어 초록 (Multilingual Abstract)

According as the members and inner and outer plates of the automobile body structure have been thinned their thickness and have become high strength, each part of the body structure has been put more severe stress condition.<br/>
Therefore, it has been increasingly required to improve the fatigue strength of the spot welded structures. As one of the improving methods for such problem, the author had previously pro­posed the method of alleviating stress concentration at nugget edge of the spot weld part and improving its fatigue strength [1]. But, because fatigue strength of the spot welded lap joint is influenced by its geometrical and mechanical factors, welding condition and etc., there needs a quantitative and systematic estimation method of them.<br/>
In this report, by considering nugget edge of the spot weld part of the spot welded lap joint subjected to tensile load to the ligament crack, fatigue strength of various spot welded lap joints was estimated with the stress intensity factor (S.I.F.) K which is fracture mechanical parameter.<br/>
It is known that evaluation of fatigue strength of the spot welded lap joint by the stress in­tensity factor (S.I.F.) K is more effective than the maximum stress (σ_ymax) at edge of the spot weld part on the center line of width of the plate.

목차 (Table of Contents)

• ABSTRACT
  
• 1.서론
  
• 2.Spot 용접부에 대한 S.I.F.K 해석의 필요성
  
• 3.FEM 요소분할의 S.I.F.K_Ⅱ에 대한 영향
  
• 4.응력확대계수 K_Ⅱ에 의한 피로강도 평가
  
• 5.결론
  
• 참고문헌