LI Xiaofeng,ZHENG Yuhan,ZHANG Dailin,et al. Research on the influence of welding defects on the fatigue life of welded joints and evaluation methods[J]. Journal of Mechanical Strength,2026,48(5):66-74.
LI Xiaofeng,ZHENG Yuhan,ZHANG Dailin,et al. Research on the influence of welding defects on the fatigue life of welded joints and evaluation methods[J]. Journal of Mechanical Strength,2026,48(5):66-74.DOI: 10.16579/j.issn.1001.9669.2026.05.008.
Research on the influence of welding defects on the fatigue life of welded joints and evaluation methods
Welding defects are the key factors which affect the welding quality and structural property. In this research
the influence and evaluation method on the fatigue life of welded joints with welding defects
which was Q450NQR1 high strength weathering steel
were discussed through tests and numerical simulation.
Methods
2
Firstly
cross joint and butt joint specimens with different defects were prepared
and the defects of the specimens were quantitatively analyzed by ultrasonic detection method in order to ensure the effectiveness of the test specimens. Secondly
fatigue tests were carried out. The influence regularity of the anti-fatigue performance of cross welded joints with different types of defects was analyzed based on the
S
-
N
curve of BS 7608:2014 standard. Finally
based on the tests
an equivalent modeling method for joints with different welding defects was proposed.
Results
2
The results show that the influence degree of different types of defects on the fatigue life of cross welded joints is as follows: undercut defect > misalignment defect > porosity defect
and the levels of anti-fatigue are F
E and D. The equivalent initial crack values of different defects were obtained by using the equivalent modeling method of welding defects. And the fitting results of different defect sizes and equivalent initial crack sizes were obtained by least square method. The research results can provide references for the fatigue life evaluation of steel welded structures with defects.
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