PSI - Issue 47

V. Giannella et al. / Procedia Structural Integrity 47 (2023) 892–900 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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2. Materials and Methods The drawings of the butt joint considered in this document were reported in Figure 1. The joint was made of two 6 mm thick low-carbon steel plates, according to Murugan et al. (1998). A single-V 60° chamfer was machined to accommodate the weld filler. The welding was split into two welding passes with the same direction. Figure 1 highlights the locations of the thermocouples that were used to record the temperatures during the welding process and the final cooling. To this aim, six thermocouples were used for monitoring the temperature variation during the welding sequence, for both plates and at three distances from the bead. The considered welding technique is the Manual Metal Arc Welding (MMAW), with welding passes performed at equal and mostly uniform speed, under room conditions, by using electrodes AWS E 6013 with diameter of 2.5 and 4 mm for first and second pass respectively. The interpass time was equal to nearly 120 s and the welding parameters are listed in Table 1.

Fig. 1. Plates dimensions (in mm) and positions of thermocouples.

Table 1. Welding parameters. Parameter

Voltage [V] Current [A]

Value for 1 st pass

Value for 2 nd pass

20

22

60-65

135-145

Electrode diameter [mm] Welding efficiency [-] Welding speed [mm/s]

2.5

4

0.75

0.75 1.66

2.5

Figure 2a-e shows the material properties for base materials and filler taken from literature (Sepe et al. (2021b c)), namely the temperature- dependent yield stress, Young’s modulus, thermal expansion coefficient, thermal conductivity and specific heat. Po isson’s ratio wa s set to 0.3 and considered as temperature independent, while the stress-strain relationship was considered as a function of temperature, see Figure 2f.