Analytical and Three-Dimensional Finite Element Investigation of Multiaxial Loading on Stress Intensity Factor of U-Shaped Spot-Welded Joints

Authors

https://doi.org/10.48313/mtei.v3i3.90

Abstract

Resistance spot-welded joints are widely used in automotive structures and are often subjected to complex loading conditions that can lead to fatigue crack initiation and growth around the weld nugget. To evaluate the fracture-mechanics behaviour and structural integrity of these joints, accurate determination of Stress Intensity Factors (SIFs) is crucial. In the present study, the SIFs for a U-shaped resistance spot welded joint under multiaxial loading are investigated by three-dimensional Finite Element Analysis (FEA) and analytical approaches. We develop a detailed numerical model of the welded sheets and weld nugget in ABAQUS to characterise the local stress field and determine the corresponding SIFs. The numerical predictions are compared with those obtained from the analytical formulations proposed by Zhang and Swellam to assess their accuracy and applicability for the configuration investigated. In addition, the influence of weld nugget diameters and sheet thicknesses on the SIFs is studied systematically. The results show that Zhang's analytical model agrees better with the finite element predictions than Swellam's formulation for the loading and geometric conditions considered. In addition, the calculated SIFs increase with increasing weld nugget diameter and sheet thickness within the investigated parameter ranges. The results provide useful insight into the mixed-mode fracture behaviour of spot-welded joints and help to assess the validity of simplified analytical approaches for multiaxially loaded welded structures.  

Keywords:

Multiaxial loading, Mixed-mode fracture, Resistance spot welding, Finite element analysis, Stress intensity factor, Weld nugget diameter, Sheet thickness

References

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Published

2026-11-02

Issue

Vol. 3 No. 3 (2026): Mechanical Technology and Engineering Insights (MTEI)

Section

Articles

How to Cite

Cornelio, O. M. ., & Masoomi, H. . (2026). Analytical and Three-Dimensional Finite Element Investigation of Multiaxial Loading on Stress Intensity Factor of U-Shaped Spot-Welded Joints. Mechanical Technology and Engineering Insights, 3(3). https://doi.org/10.48313/mtei.v3i3.90

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