PSI - Issue 59

Liubomyr Poberezhnyi et al. / Procedia Structural Integrity 59 (2024) 158–166 Liubomyr Poberezhnyi et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 6. Microstructure of welded joint zones: (a) BM; (b) BM-HAZ boundary; (c) WM; (d) WM-HAZ boundary, (e) HAZ; (f) welded macrodefect.

When comparing the calculated current densities for models with defects in the anti-corrosion insulation coating, the general patterns correspond to those for uncoated samples, although there are some differences. The current densities decrease by 15% when using the OCP measured after 24 hours, while when using the OCP measured before the potentiodynamic experiment, there is an observed increase in current density by 10-12% (Fig. 7, c, d). The main drawback of this stage of modeling is the significant difference between the current densities obtained from COMSOL models (Fig. 7) and those calculated from the results of potentiodynamic tests (Table 2). As a result, additional simulations were performed using not only the values of the OCP, but also the calculated exchange current densities as input data (Fig. 8).