PSI - Issue 61

Shahriar Afkhami et al. / Procedia Structural Integrity 61 (2024) 53–61 Shahriar Afkhami et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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- No softening was detected throughout the HAZ of the cold-formed material in this research. The absence of HAZ softening can be attributed to the slightly higher cooling rates experienced by the material in the modified joint design compared with the typical welded joints used in the steel structures. However, confirming the actual reasons behind this issue requires further research from the microstructural perspective. - The failure and plastic deformation were governed by the weld metal up to a certain level of plastic

Fig. 4. DIC results from the tensile tests carried out on the welded samples with different DOCs and R values (images along each row show the progress of each test from the test initiation to the final failure).

deformation; beyond that point, the base metal was the main contributor to the failure of the welded joint. Such a drastic change in the failure behavior of the welded joint can be attributed to the hardening behavior of the weld metal (as a low-alloy steel) being different from the base material (as a thermomechanically processed carbon steel)