PSI - Issue 60

Aritro Chatterjee et al. / Procedia Structural Integrity 60 (2024) 13–19 Aritro Chatterjee, Arpan Mandal, Anoj Giri / Structural Integrity Procedia 00 (2019) 000–000

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After estimating the relaxed Ꜫ x & Ꜫ y strains, the weld longitudinal and transverse residual stresses were calculated by following the ASTM E837-13 standard ASTM n.d.(2022). The Young modules and Poison ratio for Aluminium were taken as 70 GPa & 0.33. The Eq. 1-6 ASTM n.d.(2022) were used to find out the residual stresses. =(ε � +ε � )/2 (1) =(ε � −ε � )/2 (2) = (� � �� � � ) =− �( � �� � �) (3) = (� � �� � � ) =− � � � (4) � = − (5) � = + (6) The residual stresses σ x and σ y are found to be -100 MPa and 118 MPa respectively. In the weld longitudinal direction, compressive residual stress while in weld transverse direction, tensile residual stress was obtained. The results obtained in the study show the same trend with the available literature Brynk T et al. (2021). The results might vary due to changes in material properties and FSW process parameters. The DIC-BHD approach had been applied successfully for the residual stress measurement. 4. Conclusions The feasibility of DIC-BHD has been studied to estimate the residual stress. The paper gives the an idea to use the DIC approach to measdurme the residual stress. The shortcoming of the method had been also explored in this study.  The novel DIC method eliminates the strain rosette dependency and the material compatibility.  Displacement data near the hole are affected by the plastic deformation.  The more the numbers of speckle present on the area of interest more accurately the strain relief can be measured.  The future scope consists of the detailed study of DIC, it's accuracy and limitation for the residual stress measurement . References K. Mroczka and A. Pietras, “FSW characterization of 6082 aluminium alloys sheets,” 2009. [Online]. Available: www.archivesmse.org Yeong-Seok Lim, Sang-Hyuk Kim, Kwang-Jin Lee, "Effect of Residual Stress on the Mechanical Properties of FSW Joints with SUS409L", Advances in Materials Science and Engineering, vol. 2018, 8 pages, 2018. https://doi.org/10.1155/2018/9890234 X. Huang, Z. Liu, and H. Xie, “Recent Progress in Residual Stress Measurement Techniques,” China Acta Mechanica Solida Sinica, vol. 26, no. 6, 2013. Li, T., Shi, Q. Y., Li, H. K., Wang, W., & Cai, Z. P. (2008). Residual Stresses of Friction Stir Welded 2024-T4 Joints. Materials Science Forum, vol. 580–582, pp. 263–266, doi.org/10.4028/www.scientific.net/msf.580-582.263 Lemmen, H. J. K., Alderliesten, R. C., & Benedictus, R. (2010). Fatigue initiation behaviour throughout friction stir welded joints in AA2024-T3. International Journal of Fatigue, 32(12), 1928–1936. https://doi.org/10.1016/j.ijfatigue.2010.06.001 Lemos, G. V. B., Farina, A. B., Nunes, R. M., Cunha, P. H. C. P. Da, Bergmann, L., Santos, J. F. Dos, & Reguly, A. (2019). Residual stress characterization in friction stir welds of alloy 625. Journal of Materials Research and Technology,8(3),2528–2537. https://doi.org/10.1016/j.jmrt.2019.02.011 V. Rohilla, P. Gahlot, A. Bhoria, and S. K. Pandey, “Friction Stir Welding of Aluminum Alloy (6082): A Review,” 2017. [Online]. Available: www.ijrte.org