## 1 Introduction  
The application of corrosion inhibitors is among the most useful techniques to preserve the internal surface of steel structures, for example, tanks and pipelines, for facing corrosion, mainly in acidic environments. An acidic environment can cause various problems with metals, for example, stress corrosion cracking (SCC) in chloride-rich environments [1]. Increasing a tiny number of inhibitors without substantially varying the concentration of any corrosive agent can decrease and avoid the reaction of a metal to its environment. The benefits of inhibitors are that they reduce the level of corrosion between the corrosive agents and the surface of the metal by making a passive film on the metal surface and do not intervene in the mechanical properties of the material compared to other corrosion prevention techniques [2, 3]. Organic materials have great prospects for maximizing their role in the field of engineering [4], including for modifying corrosion processes. Corrosion inhibitors can be produced from organic and non-organic compounds. The advantages of organic compounds are they are non-toxic, affordable, renewable, and easy to produce [5, 6] but still need a lot of research to fully understand their performance and mechanism. On another side, non-organic inhibitors have already been studied and tested [7, 8, 9]. The weldment metal exhibits microstructural variations along the melted zone/weld metal (WM), heat-affected zone (HAZ), and base metal (BM) because of the welding parameters [10] and process itself [11], and it is also able to cause galvanic corrosion in steel [12]. Welding parameters significantly influence the welded joints' quality, structural integrity, and mechanical properties. Variations in parameters, such as the current type and magnitude, voltage, travel speed, electrode specifications, and shielding gas composition, directly impact crucial aspects, like the penetration depth, heat input, bead geometry, and the distribution of residual stress [10; 13; 14; 15]. Achieving optimal parameter settings is essential to attain the desired weld properties and prevent defects. Studies on shielding gas show the effects of the shielding gas content on the microstructure and toughness, underscoring the importance of precise parameter control in welding processes [16]. Differences in the microstructure, including the grain size and shape, impact the active-passive response of a corroded surface in a welded structure. For instance, a finer grain may result in a reduced localized corrosion rate but an increased rate of uniform corrosion [17]. The corrosion behavior of the HAZ region of welded X70 steel pipes in naturally aerated solutions containing 0.5 M bicarbonate and 0.01 M chloride at an atmospheric temperature of 25 \({}^{\circ}\)C have been investigated by [PERSON] et al. [18]. They found that the bainitic microstructure generated in the area that experiences fast cooling rates and high temperatures during welding such as the coarse grain HAZ (CGHAZ) and partially melted zone (PMZ) was easy to corrode as showed by their higher current density, whereas the weld metal region had the lowest corrosion current density. Several investigations within welding research have underscored the presence of solid phase transitions that notably affect stress modifications during welding [19; 20; 21; 22]. This transition commonly aligns with changes in mechanical characteristics, volumetric expansion, and Transformation-Induced Plasticity (TRIP). These modifications deeply impact the formation of residual stresses, prompting a recent focus on incorporating the effects of microstructure transformation into both experimental and simulated thermal-mechanical models for welding [23; 24; 25; 26]. The mechanical properties of each weldment zone are significantly influenced by hydrogen, with the hydrogen diffusion behavior variance and stress field distribution in each phase being crucial factors impacting hydrogen embrittlement behavior [27].