基于场强法的平板法兰角焊缝接头的疲劳寿命估算方法

Way to evaluate fatigue life of fillet weld of plate with flange based on stress field intensity

College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

摘要: 焊接接头疲劳损伤具有局部性特征.基于应力场强法的基本思想,通过对角焊接接头的场径分析,通过对法兰角焊缝接头应力集中区的弹塑性有限元计算和应力场强数值求解,得到了接头焊趾区局部应力场强.在此基础上,根据光滑试件的S-N曲线,最终得到了法兰角焊缝接头的疲劳寿命的一个估算值.该结果与局部应力应变法相比,疲劳寿命预测精度有较大提高,与试验结果吻合良好.
- 航空、航天推进系统 /
- 应力场强法 /
- 疲劳损伤 /
- 弹塑性有限元 /
- 应力集中 /
- 疲劳寿命
Abstract: The fatigue behavior of welded joint has local damage characteristics.Based on stress field intensity(SFI) theory,the field diameter of fillet welded joint was analyzed,and the stress field intensity at the weld toe of fillet weld joint of flange was calculated using elastic-plastic finite element method.Based on the calculation results and the results of S-Ncurve of smooth specimen of the same material,a fatigue life evaluation of flange fillet welded joint was obtained.The precision of fatigue life prediction with SFImethod is better than the one with the local stress-strain method,and the result is much closer to the experimental result.
- aerospace propulsion system /
- stress field intensity method /
- fatigue life fatigue damage /
- elastic-plastic finite element method /
- stress concentration /

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