한국레이저가공학회지 (Laser Solutions)
- 제11권2호
- /
- Pages.1-7
- /
- 2008
- /
- 1229-0963(pISSN)
레이저용접부의 파괴에 미치는 잔류응력의 영향
The Effect of residual stress on fracture behavior in the laser weldment
- Cho, Sung-Kyu (Hyundai Steel) ;
- Yang, Young-Soo (Chonnam National University, School of Mechanical Systems Engineering) ;
- Noh, Young-Jin (Chonnam National University Graduate School, Mechanical Engineering)
- 발행 : 2008.06.30
초록
The integrity of laser welded structures is decided in fracture strength and fatigue strength. This study made an effort to understand the fracture behavior considering residual stress. Experiments are conducted and analyses are performed to explore the influence of residual stress on fracture behavior of bead-on laser welded compact specimen. Fracture experiments are performed using ASTM 1820. The performed analyses included thermo-elasto-plastic analyses for residual stress and subsequent J-integral calculation. A modified J integral is calculated in the presence of residual stresses. The J-integral is path-independent for combination of residual stress field and stress due to mechanical loading. The results indicates that the tensile residual stress near crack front bring the low fracture load while the compressive residual stress bring the high fracture load compared to no residual stress specimen. These results quantitatively understand the influence of residual stress on fracture behavior.