ADVANCED MATERIALS & PROCESSES | JULY 2026 19 by metal arc welding using basic electrodes, selected to ensure metallurgical compatibility with the bridge material. In cases where structural elements were deformed, that is, curved, but not fractured, replacement was intentionally avoided. Instead, the material was locally heated to a cherry-red state and subsequently mechanically straightened by hammering, restoring its geometry and preserving the original material (Fig. 4). These decisions were defined prior to the application of any anticorrosive system or final coating. Prior to coating application, surface preparation was carried out by removing previous paint layers and corrosion products using mechanical tools such as flap discs, until the bare iron surface was observed (Fig. 5). This step was essential to properly assess the condition of the TABLE 1 — CHEMICAL COMPOSITION OF THE BRIDGE % Si % Cr % Ni % P % S % Mn % C % Fe Hardness 0.73 0.019 0.017 0.35 0.37 0.031 0.05 97.6 115.33 HB Fig. 3 — Oxy-cutting techniques were used to preserve the integrity of the original material. Fig. 4 — Deformed structural elements were heated and mechanically straightened by hammering. Fig. 5 — Previous paint layers and corrosion products were removed using mechanical tools before inspection. heterogeneity reflects the technological limitations of historical iron production methods. The bridge material is comparable to modern low-carbon steel 1005. This characterization was essential for defining compatible repair strategies, particularly in areas where material replacement was required due to localized damage caused by vehicle impacts[3]. The selection of replacement materials was carefully controlled to avoid significant compositional differences that could promote galvanic effects and accelerate localized corrosion. Maintaining compatibility between the original wrought iron and the replacement material was therefore a fundamental criterion. Specific repair procedures were defined to preserve the integrity of the original material. Cutting operations were carried out using oxy-cutting techniques (Fig. 3), while mechanical cutting methods with grinders were intentionally avoided to avoid unnecessary damage to the wrought iron. The welding of the replaced wrought iron parts with 1005 steel was carried out
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