Abstract
The stress intensities (stress intensity factors and J-integral) around a spot weld between sheets of dissimilar materials and different thicknesses are generally expressed by the local stresses around the spot weld. The derivations are established on an interface crack model which represents the radial cross-sections of the spot weld with the local stresses varying from point to point along the periphery of the nugget. The J-integral is determined analytically by applying the equilibrium conditions and the elementary plate theory to the model. The stress intensity factors are then separated by following a load decomposition procedure and an analytic solution to interface cracks. The thermal stress intensities are also obtained for the spot weld. Application examples are given for a tensile-shear specimen.
Similar content being viewed by others
References
Malyshev, B.M. and Salganik, R.L. (1965). The strength of adhesive joints using the theory of cracks. International Journal of Fracture 1, 114-128.
Murakami, Y. (Ed.) (1987). Stress Intensity Factors Handbook, Pergamon, Oxford, 1(8), 427-640.
Pook, L.P. (1975). Fracture mechanics analysis of the fatigue behaviour of spot welds. International Journal of Fracture 11, 173-176.
Radaj, D. (1990). Design and Analysis of Fatigue Resistant Welded Structures, Abington Publishing, Cambridge.
Radaj, D. and Zhang, S. (1991a). Stress intensity factors for spot welds between plates of unequal thickness. Engineering Fracture Mechanics 39, 391-413.
Radaj, D. and Zhang, S. (1991b). Simplified formulae for stress intensity factors of spot welds. Engineering Fracture Mechanics 40, 233-236.
Radaj, D. and Zhang, S. (1992). Stress intensity factors for spot welds between plates of dissimilar materials. Engineering Fracture Mechanics 42, 407-426.
Radaj, D. and Zhang, S. (1994). Thermal stress singularity and fracture strength at bimaterial crack tips. Mis-Matching of Welds, ESIS 17 (Edited by K.-H. Schwalbe and M. Kocak), Mechanical Engineering Publications, London, 177-194.
Rice, J.R. (1988). Elastic fracture mechanics concepts for interfacial cracks. Journal of Applied Mechanics 55, 98-103.
Rice, J.R. and Sih, G.C. (1965). Plane problems of cracks in dissimilar media. Journal of Applied Mechanics 32, 418-423.
Smith, R.A. and Cooper, J.F. (1988). Theoretical predictions of the fatigue life of shear spot welds. Fatigue of Welded Constructions, Publ The Welding Institute, Abington, Cambridge.
Suo, Z. and Hutchinson, J.W. (1990). Interface crack between two elastic layers. International Journal of Fracture 43, 1-18.
Wang, P.C. and Ewing, K.W. (1988). A J-integral Approach to Fatigue Resistance of a Tensile-shear Spot Weld. SAE Paper 880373.
Wang, P.C. and Ewing, K.W. (1991). Fracture mechanics analysis of fatigue resistance of spot welded coach-peel joints. Fatigue and Fracture of Engineering Materials and Structures 14, 915-930.
Yuuki, R. and Ohira, T. (1989). Development of the Method to Evaluate the Fatigue Life of Spot-welded Structures by Fracture Mechanics, IIW Doc. III-928-89.
Yuuki, R., Ohira, T., Nakatsukasa H. and Yi W. (1986). Fracture Mechanics Analysis of the Fatigue Strength of Various Spot Welded Joints. In symposium on Resistance Welding and Related Processes, Osaka.
Zhang, S. (1995). Forces and Stresses in Seam Welded Overlap Joints. Research Report 95-0005, Daimler-Benz AG, Stuttgart.
Zhang, S. (1997). Stress intensities at spot welds. International Journal of Fracture, 88, 167-185.
Zhang, S. (to appear). Approximate stress intensity factors and notch stresses for common spot-welded specimens. Welding Journal, submitted for publication.
Zhang, S. and Radaj, D. (1996). Forces and stresses in seam welded overlap joints derived from outer surface deformation. Engineering Fracture Mechanics 54, 743-750.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Zhang, S. Stress Intensities Derived from Stresses Around a Spot Weld. International Journal of Fracture 99, 239–257 (1999). https://doi.org/10.1023/A:1018608615567
Issue Date:
DOI: https://doi.org/10.1023/A:1018608615567