Experimental and Numerical Characterization of Residual Stresses in Tailor Welded Blanks After Springback
Residual stresses are locked-in stresses in the material that is free of external forces and thermal gradients. These stresses self-equilibrate within the cross section of the material and can result in unexpected failure if not accounted for. A good knowledge of variation of the residual stresses and its distribution is of great importance for the accurate assessment and evaluation of fatigue life of cold-formed components. The present study is based on the experimental and numerical characterization of residual stresses in the tailor welded blanks of interstitial free steel with a thickness combination of 0.8 mm × 1.5 mm after springback using a new cos α technique using a portable X-ray device (μ-X360 residual stress analyser). The longitudinally welded specimens of tailor welded blanks are tested on V-bending set-up with three different punch profile radii, i.e. 10, 12.5 and 15 mm, and the residual stress is measured on inner and outer side of the tested samples. The effect of the punch profile radius on residual stress after springback is observed to be very significant in bending of tailor welded blanks. As the punch profile radius increases, residual stress decreases for a given thickness combination. The residual stress predicted by simulations agreed well with the experimental results for all punch radii except a few cases.
KeywordsResidual stress Fatigue life Tailor welded blanks Cos α technique X-ray device Rolling direction Punch profile radius
- 1.Hutchings, M.T., Withers, P.J., Holden, T.M., Lorentzen, T.: Introduction to the Characterization of Residual Stress by Neutron Diffraction. CRC Press (2005)Google Scholar
- 2.Withers, P.J., Bhadeshia, H.: Residual stress. Part 1–measurement techniques. Mater. Sci. Technol. 17(4), 355–365 (2001)Google Scholar
- 8.Barsoum, Z.: Residual Stress Analysis and Fatigue Assessment of Welded Steel Structures. KTH, Stockholm, Sweden (2008)Google Scholar
- 11.Sasaki, T., Hirose, Y., Sasaki, K., Yasukawa, S.: Influence of image processing conditions of Debye Scherrer ring images in x-ray stress measurement using an imaging plate. Adv. X-Ray Anal. 40, 588–594 (1997)Google Scholar
- 12.Gautam, V., Kumar, D. Ravi.: Experimental and numerical investigations on springback in V-bending of tailor-welded blanks of interstitial free steel. In: Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture (2017). https://doi.org/10.1177/0954405416687146CrossRefGoogle Scholar